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1.
Proc Natl Acad Sci U S A ; 120(30): e2301478120, 2023 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-37459545

RESUMEN

The geologically rapid appearance of fossils of modern animal phyla within Cambrian strata is a defining characteristic of the history of life on Earth. However, temporal calibration of the base of the Cambrian Period remains uncertain within millions of years, which has resulted in mounting challenges to the concept of a discrete Cambrian explosion. We present precise zircon U-Pb dates for the lower Wood Canyon Formation, Nevada. These data demonstrate the base of the Cambrian Period, as defined by both ichnofossil biostratigraphy and carbon isotope chemostratigraphy, was younger than 533 Mya, at least 6 My later than currently recognized. This new geochronology condenses previous age models for the Nemakit-Daldynian (early Cambrian) and, integrated with global records, demonstrates an explosive tempo to the early radiation of modern animal phyla.


Asunto(s)
Evolución Biológica , Madera , Animales , Nevada , Fósiles , Isótopos de Carbono
2.
Nature ; 497(7451): 611-4, 2013 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-23676680

RESUMEN

Apes and Old World monkeys are prominent components of modern African and Asian ecosystems, yet the earliest phases of their evolutionary history have remained largely undocumented. The absence of crown catarrhine fossils older than ∼20 million years (Myr) has stood in stark contrast to molecular divergence estimates of ∼25-30 Myr for the split between Cercopithecoidea (Old World monkeys) and Hominoidea (apes), implying long ghost lineages for both clades. Here we describe the oldest known fossil 'ape', represented by a partial mandible preserving dental features that place it with 'nyanzapithecine' stem hominoids. Additionally, we report the oldest stem member of the Old World monkey clade, represented by a lower third molar. Both specimens were recovered from a precisely dated 25.2-Myr-old stratum in the Rukwa Rift, a segment of the western branch of the East African Rift in Tanzania. These finds extend the fossil record of apes and Old World monkeys well into the Oligocene epoch of Africa, suggesting a possible link between diversification of crown catarrhines and changes in the African landscape brought about by previously unrecognized tectonic activity in the East African rift system.


Asunto(s)
Cercopithecidae/clasificación , Fósiles , Hominidae/clasificación , Filogenia , Animales , Cercopithecidae/anatomía & histología , Historia Antigua , Hominidae/anatomía & histología , Mandíbula/anatomía & histología , Tanzanía , Diente/anatomía & histología
3.
Heredity (Edinb) ; 121(5): 422-437, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30127529

RESUMEN

Fitness landscapes map the relationship between genotypes and fitness. However, most fitness landscape studies ignore the genetic architecture imposed by the codon table and thereby neglect the potential role of synonymous mutations. To quantify the fitness effects of synonymous mutations and their potential impact on adaptation on a fitness landscape, we use a new software based on Bayesian Monte Carlo Markov Chain methods and re-estimate selection coefficients of all possible codon mutations across 9 amino acid positions in Saccharomyces cerevisiae Hsp90 across 6 environments. We quantify the distribution of fitness effects of synonymous mutations and show that it is dominated by many mutations of small or no effect and few mutations of larger effect. We then compare the shape of the codon fitness landscape across amino acid positions and environments, and quantify how the consideration of synonymous fitness effects changes the evolutionary dynamics on these fitness landscapes. Together these results highlight a possible role of synonymous mutations in adaptation and indicate the potential mis-inference when they are neglected in fitness landscape studies.


Asunto(s)
Codón , Aptitud Genética , Proteínas HSP90 de Choque Térmico/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/fisiología , Adaptación Fisiológica/genética , Teorema de Bayes , Epistasis Genética , Evolución Molecular , Genes Fúngicos , Proteínas HSP90 de Choque Térmico/química , Cadenas de Markov , Mutación , Proteínas de Saccharomyces cerevisiae/química
4.
Geostand Geoanal Res ; 42(4): 431-457, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30686958

RESUMEN

Here, we document a detailed characterisation of two zircon gemstones, GZ7 and GZ8. Both stones had the same mass at 19.2 carats (3.84 g) each; both came from placer deposits in the Ratnapura district, Sri Lanka. The U-Pb data are in both cases concordant within the uncertainties of decay constants and yield weighted mean 206Pb/238U ages (95% confidence uncertainty) of 530.26 Ma ± 0.05 Ma (GZ7) and 543.92 Ma ± 0.06 Ma (GZ8). Neither GZ7 nor GZ8 have been subjected to any gem enhancement by heating. Structure-related parameters correspond well with the calculated alpha doses of 1.48 × 1018 g-1 (GZ7) and 2.53 × 1018 g-1 (GZ8), respectively, and the (U-Th)/He ages of 438 Ma ± 3 Ma (2s) for GZ7 and 426 Ma ± 9 Ma (2s) for GZ8 are typical of unheated zircon from Sri Lanka. The mean U mass fractions are 680 µg g-1 (GZ7) and 1305 µg g-1 (GZ8). The two zircon samples are proposed as reference materials for SIMS (secondary ion mass spectrometry) U-Pb geochronology. In addition, GZ7 (Ti mass fractions 25.08 µg g-1 ± 0.18 µg g-1; 95% confidence uncertainty) may prove useful as reference material for Ti-in-zircon temperature estimates.

5.
Pers Individ Dif ; 100: 16-22, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27773957

RESUMEN

Almost 40% of individuals with eating disorders have a comorbid addiction. The current study examined weight/shape concerns as a potential moderator of the relation between the hypothesized latent factor "addiction vulnerability" (i.e., impairments in reward sensitivity, affect regulation and impulsivity) and binge eating. Undergraduate women (n=272) with either high or low weight/shape concerns completed self-report measures examining reward sensitivity, emotion regulation, impulsivity and disordered (binge) eating. Results showed that (1) reward sensitivity, affect regulation and impulsivity all loaded onto a latent "addiction vulnerability" factor for both women with high and with low weight/shape concerns, (2) women with higher weight/shape concerns reported more impairment in these areas, and (3) weight/shape concerns moderated the relation between addiction vulnerability and binge eating. These findings suggest that underlying processes identified in addiction are present in individuals who binge eat, though weight/shape concerns may be a unique characteristic of disordered eating.

6.
J Environ Qual ; 42(3): 660-5, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23673931

RESUMEN

In developing the national biosolids recycling rule (Title 40 of the Code of Federal Regulation Part 503 or Part 503), the USEPA conducted deterministic risk assessments whose results indicated that the probability of groundwater impairment associated with biosolids recycling was insignificant. Unfortunately, the computational capabilities available for performing risk assessments of pollutant fate and transport at that time were limited. Using recent advances in USEPA risk assessment methodology, the present study evaluates whether the current national biosolids pollutant limits remain protective of groundwater quality. To take advantage of new risk assessment approaches, a computer-based groundwater risk characterization screening tool (RCST) was developed using USEPA's Multimedia, Multi-pathway, Multi-receptor Exposure and Risk Assessment program. The RCST, which generates a noncarcinogenic human health risk estimate (i.e., hazard quotient [HQ] value), has the ability to conduct screening-level risk characterizations. The regulated heavy metals modeled in this study were As, Cd, Ni, Se, and Zn. Results from RCST application to biosolids recycling sites located in Yakima County, Washington, indicated that biosolids could be recycled at rates as high as 90 Mg ha, with no negative human health effects associated with groundwater consumption. Only under unrealistically high biosolids land application rates were public health risks characterized as significant (HQ ≥ 1.0). For example, by increasing the biosolids application rate and pollutant concentrations to 900 Mg ha and 10 times the regulatory limit, respectively, the HQ values varied from 1.4 (Zn) to 324.0 (Se). Since promulgation of Part 503, no verifiable cases of groundwater contamination by regulated biosolids pollutants have been reported.


Asunto(s)
Agua Subterránea , Reciclaje , Monitoreo del Ambiente , Humanos , Metales Pesados , Modelos Teóricos , Medición de Riesgo
7.
PLoS One ; 18(9): e0291074, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37756287

RESUMEN

The Pilbara craton of northwestern Australia is known for what were, when reported, the oldest known microfossils and paleosols on Earth. Both interpretations are mired in controversy, and neither remain the oldest known. Both the microfossils and the paleosols have been considered hydrothermal artefacts: carbon films of vents and a large hydrothermal cupola, respectively. This study resampled and analyzed putative paleosols within and below the Strelley Pool Formation (3.3 Ga), at four classic locations: Strelley Pool, Steer Ridge, Trendall Ridge, and Streckfuss, and also at newly discovered outcrops near Marble Bar. The same sequence of sedimentary facies and paleosols was newly recognized unconformably above the locality for microfossils in chert of the Apex Basalt (3.5 Ga) near Marble Bar. The fossiliferous Apex chert was not a hydrothermal vein but a thick (15 m) sedimentary interbed within a sequence of pillow basalts, which form an angular unconformity capped by the same pre-Strelley paleosol and Strelley Pool Formation facies found elsewhere in the Pilbara region. Baritic alluvial paleosols within the Strelley Pool Formation include common microfossil spindles (cf. Eopoikilofusa) distinct from marine microfossil communities with septate filaments (Primaevifilum) of cherts in the Apex and Mt Ada Basalts. Phosphorus and iron depletion in paleosols within and below the Strelley Pool Formation are evidence of soil communities of stable landscapes living under an atmosphere of high CO2 (2473 ± 134 ppmv or 8.8 ± 0.5 times preindustrial atmospheric level of 280 ppm) and low O2 (2181 ± 3018 ppmv or 0.01 ± 0.014 times modern).


Asunto(s)
Artefactos , Carbonato de Calcio , Humanos , Australia Occidental , Facies , Australia
8.
Sci Rep ; 13(1): 5485, 2023 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-37016151

RESUMEN

The end-Triassic extinction (ETE) event represents one of the 'big five' episodes of mass extinction. The leading hypothesis for the cause of the ETE is the intrusion of voluminous magmas of the Central Atlantic Magmatic Province (CAMP) into carbon-rich sediments of two South American sedimentary basins, around 201.5 Ma. The timing of dikes and sills emplacement, however, must be considered in light of age models from CAMP rocks occurring in North America. In this work, we present new high-precision ages for critical samples in NE Brazil (201.579 ± 0.057 Ma) and Canada (201.464 ± 0.017 Ma), in order to evaluate how the South and North American magmatic events compare at the 100-ka level, and to the ETE timing. We also discuss inter-laboratory reproducibility of high-precision CAMP ages, including the 230Th disequilibrium corrections that are made to zircon U-Pb dates. Our findings in this newly discovered extension of the CAMP large igneous province in NE Brazil support the hypothesis that the CAMP may be responsible for the ETE through the triggering of greenhouse gas release from magma-evaporite interactions (contact metamorphism) in the South American basins.

9.
J Nerv Ment Dis ; 200(6): 480-5, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22652610

RESUMEN

The DSM-IV diagnostic criteria for major depressive disorder exclude bereavement-related depressive episodes that are brief and lack certain severe symptoms and are thus better explained as normal grief responses. However, the DSM-5 Task Force proposes to eliminate this exclusion because of a lack of evidence that such episodes differ relevantly from standard major depression. Using the two-wave longitudinal Epidemiologic Catchment Area Study, we compared 1-yr depression recurrence rates at wave 2 of four groups at wave 1 baseline: (1) those with no history of depressive disorder (n = 18,239), (2) those who had only lifetime excludable bereavement-related depression (n = 25), (3) those with brief-episode (≤ 2 months duration) lifetime standard depressive disorder (n = 446), and (4) those with nonbrief lifetime standard depressive disorder (n = 581). The recurrence rate in the excludable-depression group (3.7%) was not significantly different from the no-history group (1.7%) but was significantly and substantially lower than in the brief and nonbrief standard depression groups (14.4% and 16.2%, respectively). These findings confirm findings reported by Mojtabai (Arch Gen Psychiatry 68:920-928, 2011) using a different data set and time frame and thus substantially strengthen the support for the validity of bereavement exclusion and for its preservation in the DSM-5.


Asunto(s)
Aflicción , Depresión/psicología , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Humanos , Masculino
10.
Ecol Evol ; 12(7): e9046, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35813923

RESUMEN

Mutational meltdown describes an eco-evolutionary process in which the accumulation of deleterious mutations causes a fitness decline that eventually leads to the extinction of a population. Possible applications of this concept include medical treatment of RNA virus infections based on mutagenic drugs that increase the mutation rate of the pathogen. To determine the usefulness and expected success of such an antiviral treatment, estimates of the expected time to mutational meltdown are necessary. Here, we compute the extinction time of a population under high mutation rates, using both analytical approaches and stochastic simulations. Extinction is the result of three consecutive processes: (a) initial accumulation of deleterious mutations due to the increased mutation pressure; (b) consecutive loss of the fittest haplotype due to Muller's ratchet; (c) rapid population decline toward extinction. We find accurate analytical results for the mean extinction time, which show that the deleterious mutation rate has the strongest effect on the extinction time. We confirm that intermediate-sized deleterious selection coefficients minimize the extinction time. Finally, our simulations show that the variation in extinction time, given a set of parameters, is surprisingly small.

11.
Sci Adv ; 8(47): eadc9430, 2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36417531

RESUMEN

During the Cryogenian (720 to 635 Ma ago) Snowball Earth glaciations, ice extended to sea level near the equator. The cause of this catastrophic failure of Earth's thermostat has been unclear, but previous geochronology has suggested a rough coincidence of glacial onset with one of the largest magmatic episodes in the geological record, the Franklin large igneous province. U-Pb geochronology on zircon and baddeleyite from sills associated with the paleo-equatorial Franklin large igneous province in Arctic Canada record rapid emplacement between 719.86 ± 0.21 and 718.61 ± 0.30 Ma ago, 0.9 to 1.6 Ma before the onset of widespread glaciation. Geologic observations and (U-Th)/He dates on Franklin sills are compatible with major post-Franklin exhumation, possibly due to development of mafic volcanic highlands on windward equatorial Laurentia and increased global weatherability. After a transient magmatic CO2 flux, long-term carbon sequestration associated with increased weatherability could have nudged Earth over the threshold for runaway ice-albedo feedback.

12.
J Nerv Ment Dis ; 199(2): 66-73, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21278534

RESUMEN

The DSM's major-depression "bereavement exclusion" eliminates bereavement-related depressive episodes (BRDs) from diagnosis unless they are "complicated" by prolonged duration or certain severe symptoms. The exclusion was substantially narrowed in DSM-IV to decrease false-negative diagnoses, but the impact of this change remains unknown. We divided BRDs in the National Comorbidity Survey into uncomplicated versus complicated categories using broader DSM-III-R and narrower DSM-IV exclusion criteria. Using 6 pathology validators (symptom number, melancholic depression, suicide attempt, interference with life, medication for depression, and hospitalization for depression), we compared the validity of the 2 exclusion criteria sets using 2 tests: (1) which criteria set yielded less pathological uncomplicated cases or more pathological complicated cases; (2) which yielded the largest separation between uncomplicated and complicated pathology levels. Results of both tests indicated that the narrower DSM-IV criteria substantially decreased the exclusion's validity. These results suggest caution regarding the current proposal to eliminate the bereavement exclusion in DSM-5.


Asunto(s)
Aflicción , Trastorno Depresivo Mayor/diagnóstico , Trastorno Depresivo Mayor/epidemiología , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Adolescente , Adulto , Antidepresivos/administración & dosificación , Comorbilidad , Depresión/epidemiología , Trastorno Depresivo Mayor/tratamiento farmacológico , Trastorno Depresivo Mayor/psicología , Diagnóstico Diferencial , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Intento de Suicidio/estadística & datos numéricos , Encuestas y Cuestionarios , Factores de Tiempo , Estados Unidos/epidemiología
13.
Nat Commun ; 12(1): 6299, 2021 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-34728621

RESUMEN

The main phase of silicic volcanism from the Afro-Arabian large igneous province preserves some of the largest volcanic eruptions on Earth, with six units totaling >8,600 km3 dense rock equivalent (DRE). The large volumes of rapidly emplaced individual eruptions present a case study for examining the tempo of voluminous silicic magma generation and emplacement. Here were report high-precision 206Pb/238U zircon ages and show that the largest sequentially dated eruptions occurred within 48 ± 34 kyr (29.755 ± 0.023 Ma to 29.707 ± 0.025 Ma), yielding the highest known long-term volumetric extrusive rate of silicic volcanism on Earth. While these are the largest known sequential silicic supereruptions, they did not cause major global environmental change. We also provide a robust tie-point for calibration of the geomagnetic polarity timescale by integrating 40Ar/39Ar data with our 206Pb/238U ages to yield new constraints on the duration of the C11n.1r Subchron.

14.
Water Environ Res ; 82(5): 455-61, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20480767

RESUMEN

Biosolids land application was demonstrated to be a potentially cost-effective means for restoring forage productivity and enhancing soil-moisture-holding capacity on disturbed rangelands. By land-applying aerobically digested, anaerobically digested, composted, and lime-stabilized biosolids on rangeland test plots at rates of up to 20 times (20X) the estimated nitrogen-based agronomic rate, forage yields were found to increase from 132.8 kg/ha (118.2 lb/ac) (control plots) to 1182.3 kg/ha (1052.8 lb/ac). Despite the environmental benefits associated with increased forage yield (e.g., reduced soil erosion, improved drainage, and enhanced terrestrial carbon sequestration), the type of forage generated both before and after biosolids land application was found to be dominated by invasive weeds, all of which were characterized as having fair to poor nutritional value. Opportunistic and shallow rooting invasive weeds not only have marginal nutritional value, they also limit the establishment of native perennial grasses and thus biodiversity. Many of the identified invasive species (e.g., Cheatgrass) mature early, a characteristic that significantly increases the fuel loads that support the increased frequency and extent of western wildfires.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Fertilizantes , Desarrollo de la Planta , Eliminación de Residuos Líquidos/métodos , Aguas del Alcantarillado , Suelo , Estados Unidos , Agua
15.
Arch Gen Psychiatry ; 64(4): 433-40, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17404120

RESUMEN

CONTEXT: Symptoms of intense bereavement-related sadness may resemble those of major depressive disorder (MDD) but may not indicate a mental disorder. To avert false-positive diagnoses, DSM criteria for MDD exclude uncomplicated bereavement of brief duration and modest severity. However, the DSM does not similarly exempt depressive reactions to other losses, even when they are uncomplicated in duration and severity. OBJECTIVE: To test the validity of the DSM exclusion of uncomplicated depressive symptoms only in response to bereavement but not in response to other losses. DESIGN: Community-based epidemiological study. PARTICIPANTS: From the National Comorbidity Survey (NCS) of 8098 persons aged 15 to 54 years representative of the US population, we identified individuals who met MDD symptom criteria and whose MDD episodes were triggered by either bereavement (n = 157) or other loss (n = 710). Intervention We divided the bereavement and other loss trigger groups into uncomplicated and complicated cases by applying the NCS algorithm for uncomplicated bereavement to the reactions to other losses. We then compared uncomplicated bereavement and uncomplicated reactions to other losses on a variety of disorder indicators and symptoms. MAIN OUTCOME MEASURES: Nine disorder indicators, as follows: number of symptoms, melancholic depression, suicide attempt, duration of symptoms, interference with life, recurrence, and 3 service use variables. RESULTS: Episodes of uncomplicated depression triggered by bereavement and by other loss have similar symptom profiles and are not significantly different for 8 of 9 disorder indicators. Moreover, uncomplicated reactions, whether triggered by bereavement or other loss, are significantly lower than complicated reactions on almost all disorder indicators. CONCLUSION: The NCS data do not support the validity of uniquely excluding uncomplicated bereavement but not uncomplicated reactions to other losses from MDD diagnosis.


Asunto(s)
Aflicción , Trastorno Depresivo Mayor/diagnóstico , Reacciones Falso Positivas , Acontecimientos que Cambian la Vida , Adolescente , Adulto , Algoritmos , Comorbilidad , Recolección de Datos , Trastorno Depresivo Mayor/epidemiología , Diagnóstico Diferencial , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica/estadística & datos numéricos , Reproducibilidad de los Resultados , Estados Unidos
16.
J Psychosom Obstet Gynaecol ; 28(4): 219-29, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17852659

RESUMEN

OBJECTIVE: The purpose of this research was to validate the Hyperemesis Beliefs Scale (HBS), a new instrument for assessing patient perception factors of hyperemesis gravidarum (HG) that influence reported patient satisfaction with medical care. METHODS: Patients' beliefs and their perception of their physicians' beliefs about the causal explanations of HG, seriousness of the illness, and the impact of the illness upon patients' daily lives were determined using a newly developed hyperemesis beliefs scale (HBS) in a sample of 96 women. Exploratory factor analyses of the patient and physician versions of the HBS were performed separately using principal factor analysis extraction and oblique rotation in SPSS. RESULTS: Exploratory factor analyses of patient and physician versions of the HBS demonstrated broad support for the hypothesized factor structure. However, two key differences appeared in the two versions of the HBS. First, the patient items exhibited two causal factors (general and personal), whereas the physician items showed only a single causal factor. Second, in the patient version, items assessing the impact of HG on the babies' health loaded separately from the rest of the items in the HBS, whereas the analyses of the corresponding physician items indicated that the baby items loaded well on the degree of seriousness factor. CONCLUSION: This scale may be of value in facilitating further research on HG illness representations, patient-physician relationship and patient satisfaction. Specifically, the HBS design provides data to show whether patient-physician agreement on particular measures is associated with better patient satisfaction outcomes.


Asunto(s)
Hiperemesis Gravídica/psicología , Náusea/psicología , Aceptación de la Atención de Salud/psicología , Aceptación de la Atención de Salud/estadística & datos numéricos , Percepción , Encuestas y Cuestionarios , Adulto , Actitud Frente a la Salud , Análisis Factorial , Femenino , Humanos , Satisfacción del Paciente , Pacientes/psicología , Relaciones Médico-Paciente , Embarazo , Índice de Severidad de la Enfermedad , Estados Unidos
17.
J Affect Disord ; 208: 325-329, 2017 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-27810714

RESUMEN

BACKGROUND: Uncomplicated major depressive disorder (UMDD) is defined as MDD that does not include any of six pathosuggestive features: more than six months duration, marked functional impairment, sense of worthlessness, suicidal ideation, psychotic ideation, and psychomotor retardation. Complicated MDD (CMDD) includes all episodes containing one or more of these features. UMDD has been shown to be lower than CMDD and indistinguishable from no-MDD-history on predictive pathology validators. This study's purpose is to establish where on the number-of-symptoms depressive continuum UMDD is located, using the criterion of predictive validity. METHODS: Using two-wave longitudinal community data, seven baseline depression history subgroups were identified: no MDD symptoms (n=23,214), one MDD screener symptom (n=609), subthreshold or "minor" depression (mD; 2-4 MDD symptoms; n=2,623), UMDD (n=505), and complicated MDD with 5-6 symptoms (n=1,106), 7 symptoms (n=1,200), and 8-9 symptoms (n=2,408). Predictive validity was evaluated by four follow-up variables: major depressive episode; generalized anxiety disorder; suicide attempt; and manic/hypomanic episode. RESULTS: UMDD predictive pathology validator rates are not significantly different from rates for subthreshold mD but significantly different from those for all other depression categories; UMDD is higher in symptoms but lower in validator levels than 5-6 symptom CMDD. LIMITATIONS: Baseline and follow-up diagnoses were based on respondents' fallible retrospective symptom reports in response to a lay-administered structured questionnaire, which may not yield diagnoses comparable to clinicians' assessments. CONCLUSION: Uncomplicated MDD's follow-up outcomes resemble subthreshold depression, not CMDD, even when CMDD has less symptoms. Clinical decisions should reflect the relatively benign prognosis of uncomplicated MDD.


Asunto(s)
Trastorno Depresivo Mayor/diagnóstico , Adolescente , Adulto , Trastornos de Ansiedad/complicaciones , Trastorno Bipolar/complicaciones , Depresión/complicaciones , Trastorno Depresivo Mayor/complicaciones , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Pronóstico , Índice de Severidad de la Enfermedad , Intento de Suicidio , Adulto Joven
18.
J Affect Disord ; 212: 101-109, 2017 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-28157549

RESUMEN

BACKGROUND: "Complicated" subthreshold depression (CsD) includes at least one of six pathosuggestive "complicated" symptoms: >6 months duration, marked role impairment, sense of worthlessness, suicidal ideation, psychotic ideation, and psychomotor retardation. "Uncomplicated" subthreshold depression (UsD) has no complicated features. Whereas studies show that complicated (CMDD) versus uncomplicated (UMDD) major depression differ substantially in severity and prognosis, UsD and CsD severity has not been previously compared. This study evaluates UsD and CsD pathology validator levels and examines whether the complicated/uncomplicated distinction offers incremental concurrent validity over the standard number-of-symptoms dimension as a depression severity measure. METHODS: Using nationally representative community data from the National Comorbidity Survey, seven depression lifetime history subgroups were identified: one MDD screener symptom (n=1432); UsD (n=430); CsD (n=611); UMDD (n=182); and CMDD with 5-6 symptoms (n=518), 7 symptoms (n=217), and 8-9 symptoms (n=291). Severity was evaluated using five concurrent pathology validators: suicide attempt, interference with life, help seeking, hospitalization, and generalized anxiety disorder. RESULTS: CsD validator levels are substantially higher than both UsD and UMDD levels, and similar to mild CMDD, disconfirming the "monotonicity thesis" that severity increase with symptom number. Complicated/uncomplicated status predicts severity, and when complicatedness is controlled, number of symptoms no longer predicts validator levels. LIMITATIONS: Diagnoses were based on respondents' fallible retrospective symptom reports during a lay-administered structured interview, which may not yield diagnoses comparable to clinicians' assessments. CONCLUSION: CsD is more severe than UsD and comparable to mild MDD. Complicated status more validly indicates depression severity than the standard number-of-symptoms measure.


Asunto(s)
Trastorno Depresivo/clasificación , Adolescente , Adulto , Comorbilidad , Trastorno Depresivo/psicología , Trastorno Depresivo Mayor/clasificación , Femenino , Encuestas Epidemiológicas , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Autoinforme , Intento de Suicidio/estadística & datos numéricos , Estados Unidos , Adulto Joven
19.
J Psychosom Obstet Gynaecol ; 27(1): 49-57, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16752876

RESUMEN

OBJECTIVE: To examine the relationship between patients' perceptions of the patient-physician relationship and patients' satisfaction with the overall medical care received from their physicians in the treatment of hyperemesis gravidarum (HG). METHODS: This study investigated patients' beliefs and their views of their physicians' beliefs about the causal explanation of HG, the seriousness of the illness, and the impact of the illness upon patients' daily lives. Also examined were the extent to which patients' beliefs were congruent with their perception of their physicians' beliefs, and patients' ratings of the humanistic characteristics of physicians they deemed important. Ninety-six respondents who had experienced at least one hospitalization from January 1993 through April 1997 responded to interview questions focusing on their HG illness experience. Using both quantitative and qualitative methodological approaches, a path model of patient perception factors associated with patient satisfaction was tested. RESULTS: Perceived shared beliefs about the etiology of HG for a particular patient's illness were more important direct contributing factors of satisfaction than were the specific causal explanations. The length of the patient-physician relationship provided important indirect effects on patient satisfaction; three key mediating variables were patients' perceptions about physician humanism and perceived agreement about the cause and impact of HG. Pertinent qualitative findings are provided as additional sources of information to supplement the quantitative results. CONCLUSION: Knowledge of the patient-physician relationship factors that influence HG women's satisfaction can be used to enhance service delivery and may ultimately improve perinatal outcomes.


Asunto(s)
Actitud , Hiperemesis Gravídica , Satisfacción del Paciente , Pacientes/psicología , Relaciones Médico-Paciente , Adulto , Femenino , Humanos , Hiperemesis Gravídica/psicología , Hiperemesis Gravídica/terapia , Educación del Paciente como Asunto , Embarazo , Complicaciones del Embarazo , Encuestas y Cuestionarios
20.
Addiction ; 110(6): 931-42, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25622535

RESUMEN

AIMS: To formulate harmful dysfunction (HD) diagnostic criteria for alcohol use disorder (AUD) and test whether they increase validity relative to standard DSM criteria, as evidenced by lowered prevalence, increased validator levels including service use, severity and family history and enhanced specificity. DESIGN: DSM-IV AUD, DSM-IV dependence, DSM-5 AUD and HD AUD definitions were compared on eight validity related tests using nationally representative community data. SETTING: United States. PARTICIPANTS: National Epidemiologic Survey of Alcoholism and Related Conditions (NESARC) respondents, aged 18-54 years (wave 1, n = 29 673; wave 2, n = 24 244). MEASURES: NESARC DSM-IV and DSM-5 criteria were taken from published studies. Whereas DSM-5 diagnosis requires any two AUD symptoms, HD criteria were constructed from NESARC items to require symptoms of both impaired-control dysfunction [withdrawal, drink to prevent/stop withdrawal, cannot stop/reduce drinking, or craving (wave 2 only)] and harm (sacrificed important activities, problems caring for home/family, job/school problems, health problems, psychological problems or problems with family/friends). Validators included service use, severity and family history, among others. Specificity was tested using a teen transient drinker criterion group. FINDINGS: Compared with DSM-5 AUD (DSM-IV results were similar), HD criteria yielded lower prevalence (95% confidence intervals): HD life-time 6.7% (6.2, 7.2%), 1-year 2.3% (2.0, 2.5%); and DSM-5 life-time 38.2% (36.5, 39.9%), 1-year 12.4% (11.7, 13.1%). HD AUD was higher than DSM-5 on pathology validators, including: life-time alcohol-related service use: HD 41.0% (38.1, 43.9%), DSM-5 11.5% (10.7, 12.3%); severity (number of life-time alcohol symptoms): HD 20.8 (20.4, 21.2), DSM-5 10.6 (10.4, 10.8); and family history of alcohol problems: HD 50.1% (47.3, 52.9), DSM-5 32.8% (31.6, 34.0). HD criteria eliminated 83% of a DSM-5 teen transient drinker false-positives criterion group. CONCLUSIONS: Prevalence estimates of alcohol use disorder are lowered and diagnostic validity improved when using 'harmful dysfunction' diagnostic criteria compared with standard DSM criteria, partly by reducing misdiagnosis of teenage transient drinkers.


Asunto(s)
Trastornos Relacionados con Alcohol/diagnóstico , Adolescente , Adulto , Distribución por Edad , Consumo de Bebidas Alcohólicas/epidemiología , Trastornos Relacionados con Alcohol/epidemiología , Trastornos Relacionados con Alcohol/etiología , Alcoholismo/diagnóstico , Alcoholismo/epidemiología , Alcoholismo/etiología , Ansia , Errores Diagnósticos/prevención & control , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Psicológicos , Prevalencia , Escalas de Valoración Psiquiátrica , Reproducibilidad de los Resultados , Asunción de Riesgos , Terminología como Asunto , Estados Unidos/epidemiología , Adulto Joven
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