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1.
Ecol Lett ; 17(5): 574-82, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24818236

RESUMEN

Whole-genome duplication (polyploidy) occurs frequently and repeatedly within species, often forming new lineages that contribute to biodiversity, particularly in plants. Establishment and persistence of new polyploids may be thwarted by competition with surrounding diploids; however, climatic niche shifts, where polyploids occupy different niches than diploid progenitors, may help polyploids overcome this challenge. We tested for climatic niche shifts between cytotypes using a new ordination approach and an unprecedentedly large data set containing young, conspecific diploids and polyploids. Despite expectations of frequent niche shifts, we show evidence for alternative patterns, such as niche conservatism and contraction, rather than a prevalent pattern of niche shifts. In addition, we explore how interpreting climatic niches plotted on environmental niche (principal component) axes can generate hypotheses about processes underlying niche dynamics. Dispersal capabilities or other life-history traits, rather than shifts to new climatic niches, could better explain polyploid persistence in the long term.


Asunto(s)
Clima , Diploidia , Ecosistema , Poliploidía , Biodiversidad , Fenómenos Fisiológicos de las Plantas , Plantas/genética
2.
J Evol Biol ; 22(6): 1275-83, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19453371

RESUMEN

Host-associated differentiation (HAD) appears to be an important driver of diversification in the hyperdiverse phytophagous and parasitoid insects. The gallmaking moth Gnorimoschema gallaesolidaginis has undergone HAD on two sympatric goldenrods (Solidago), and HAD has also been documented in its parasitoid Copidosoma gelechiae, with the intriguing suggestion that differentiation has proceeded independently in multiple populations. We tested this suggestion with analysis of Amplified Fragment Length Polymorphism (AFLP) markers for C. gelechiae collections from the midwestern and northeastern United States and eastern Canada. AFLP data were consistent with the existence of HAD, with between-host F(ST) significant before Bonferroni correction in two of seven sympatric populations. amova analysis strongly rejected a model of HAD with a single historical origin, and thus supported the repeated-HAD hypothesis. Copidosoma gelechiae shows significant host-associated divergence at a number of allozyme loci (Stireman et al., 2006), but only weak evidence via AFLPs for genome-wide differentiation, suggesting that this species is at a very early stage of HAD.


Asunto(s)
Evolución Biológica , Interacciones Huésped-Parásitos , Mariposas Nocturnas/parasitología , Avispas/genética , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Animales , Genoma de los Insectos , Geografía , Great Lakes Region , Isoenzimas
3.
Mol Phylogenet Evol ; 21(1): 117-27, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11603942

RESUMEN

The pollination mutualism between yucca moths and yuccas highlights the potential importance of host plant specificity in insect diversification. Historically, one pollinator moth species, Tegeticula yuccasella, was believed to pollinate most yuccas. Recent phylogenetic studies have revealed that it is a complex of at least 13 distinct species, eight of which are specific to one yucca species. Moths in the closely related genus Prodoxus also specialize on yuccas, but they do not pollinate and their larvae feed on different plant parts. Previous research demonstrated that the geographically widespread Prodoxus quinquepunctellus can rapidly specialize to its host plants and may harbor hidden species diversity. We examined the phylogeographic structure of P. quinquepunctellus across its range to compare patterns of diversification with six coexisting pollinator yucca moth species. Morphometric and mtDNA cytochrome oxidase I sequence data indicated that P. quinquepunctellus as currently described contains two species. There was a deep division between moth populations in the eastern and the western United States, with limited sympatry in central Texas; these clades are considered separate species and are redescribed as P. decipiens and P. quinquepunctellus (sensu stricto), respectively. Sequence data also showed a lesser division within P. quinquepunctellus s.s. between the western populations on the Colorado Plateau and those elsewhere. The divergence among the three emerging lineages corresponded with major biogeographic provinces, whereas AMOVA indicated that host plant specialization has been relatively unimportant in diversification. In comparison, the six pollinator species comprise three lineages, one eastern and two western. A pollinator species endemic to the Colorado Plateau has evolved in both of the western lineages. The east-west division and the separate evolution of two Colorado Plateau pollinator species suggest that similar biogeographic factors have influenced diversification in both Tegeticula and Prodoxus. For the pollinators, however, each lineage has produced a monophagous species, a pattern not seen in P. quinquepunctellus.


Asunto(s)
Mariposas Nocturnas/genética , Filogenia , Análisis de Varianza , Animales , ADN/química , ADN/genética , ADN Mitocondrial/genética , Complejo IV de Transporte de Electrones/genética , Evolución Molecular , Femenino , Geografía , Haplotipos , Masculino , Datos de Secuencia Molecular , Mariposas Nocturnas/anatomía & histología , Mariposas Nocturnas/clasificación , Plantas/parasitología , Polen/fisiología , Análisis de Secuencia de ADN , Estados Unidos
4.
Mol Ecol ; 10(5): 1247-53, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11380881

RESUMEN

Tegeticula maculata is one of the most ancient and morphologically variable lineages within the yucca moths, yet has apparently undergone little diversification in comparison with much younger yucca moth lineages that have rapidly diversified. A phylogeographic approach was used to determine the number of independent lineages within T. maculata and to examine whether these patterns corresponded with morphological differences between its subspecies maculata and extranea. Phylogenetic analysis of mitochondrial DNA sequence variation indicated that the two subspecies are in separate clades, but there was also an equally deep split within subspecies maculata. There was no evidence for gene flow among regions and there was considerable substructure within clades. The phylogeographic structure of moth populations among and within subspecies can be explained in part by historical biogeographic boundaries and increasingly patchy postglacial distribution of the exclusive host plant, Hesperoyucca whipplei. Local specialization and co-adaptation would be possible in the absence of apparent gene flow, yet gross morphological divergence is limited to the very old split between the subspecies. Sorting of ancient mitochondrial lineages followed by local genetic differentiation may explain the pattern of high genetic structure with limited speciation.


Asunto(s)
Genética de Población , Mariposas Nocturnas/genética , Filogenia , Animales , California , ADN Mitocondrial/genética , Complejo IV de Transporte de Electrones/genética , Haplotipos , Modelos Genéticos , Datos de Secuencia Molecular , Fenómenos Fisiológicos de las Plantas
5.
J Urol ; 163(3): 888-93, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10688001

RESUMEN

PURPOSE: Female sexual dysfunction is highly prevalent but not well defined or understood. We evaluated and revised existing definitions and classifications of female sexual dysfunction. MATERIALS AND METHODS: An interdisciplinary consensus conference panel consisting of 19 experts in female sexual dysfunction selected from 5 countries was convened by the Sexual Function Health Council of the American Foundation for Urologic Disease. A modified Delphi method was used to develop consensus definitions and classifications, and build on the existing framework of the International Classification of Diseases-10 and DSM-IV: Diagnostic and Statistical Manual of Mental Disorders of the American Psychiatric Association, which were limited to consideration of psychiatric disorders. RESULTS: Classifications were expanded to include psychogenic and organic causes of desire, arousal, orgasm and sexual pain disorders. An essential element of the new diagnostic system is the "personal distress" criterion. In particular, new definitions of sexual arousal and hypoactive sexual desire disorders were developed, and a new category of noncoital sexual pain disorder was added. In addition, a new subtyping system for clinical diagnosis was devised. Guidelines for clinical end points and outcomes were proposed, and important research goals and priorities were identified. CONCLUSIONS: We recommend use of the new female sexual dysfunction diagnostic and classification system based on physiological as well as psychological pathophysiologies, and a personal distress criterion for most diagnostic categories.


Asunto(s)
Disfunciones Sexuales Fisiológicas/clasificación , Disfunciones Sexuales Fisiológicas/diagnóstico , Femenino , Humanos
6.
J Consult Clin Psychol ; 67(4): 547-54, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10450625

RESUMEN

Adult smokers (N = 253) without clinically significant depression were randomized on a double-blind basis to receive fluoxetine (30 or 60 mg daily) or a placebo for 10 weeks in combination with cognitive-behavioral therapy (CBT). It was predicted that fluoxetine would selectively benefit smokers with higher baseline depression, nicotine dependence, and weight concern and lower self-efficacy about quitting smoking. Among those who completed the prescribed treatment regimen, baseline depression scores moderated the treatment response. Logistic regression analyses showed that 1 and 3 months after the quit date, fluoxetine increased the likelihood of abstinence, as compared with placebo, among smokers with minor depression but not among those with little or no depression. Results suggests that, as an adjunct to CBT, fluoxetine enhances cessation by selectively benefiting medication-compliant smokers who display even subclinical levels of depression.


Asunto(s)
Antidepresivos de Segunda Generación/administración & dosificación , Fluoxetina/administración & dosificación , Cese del Hábito de Fumar/psicología , Adolescente , Adulto , Anciano , Terapia Cognitivo-Conductual , Terapia Combinada , Depresión/diagnóstico , Depresión/terapia , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
7.
Evolution ; 53(4): 1114-1127, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28565509

RESUMEN

In many polyploid species, polyploids often have different suites of floral traits and different flowering times than their diploid progenitor species. We hypothesized that such differences in floral traits in polyploids may subsequently affect their interactions with pollinating and other insect visitors. We measured floral morphology and flowering phenology in 14 populations of diploid and autotetraploid Heuchera grossulariifolia Rydb. (Saxifragaceae), determined if repeated evolution of independent polyploid lineages resulted in differentiation in floral morphology among those lineages, and ascertained if there was a consistent pattern of differentiation among genetically similar diploid and autotetraploid populations. In addition, we evaluated the differences in suites of floral visitors within a natural community where diploids and autotetraploids occur sympatrically. Overall, flowers of autotetraploid plants were larger and shaped differently than those of diploids, had a different flowering phenology than that of diploids, and attracted different suites of floral visitors. In comparison with flowers of diploids, tetraploid floral morphology varied widely from pronounced differences between cytotypes in some populations to similar flower shapes and sizes between ploidal levels in other populations. Observations of floral visitors to diploids and autotetraploids in a natural sympatric population demonstrated that the cytotypes had different suites of floral visitors and six of the 15 common visitors preferentially visited one ploidy more frequently. Moreover, we also found that floral morphology differed among independent autotetraploid origins, but there was no consistent pattern of differentiation between genetically similar diploid and autotetraploid populations. Hence, the results suggest that the process of polyploidization creates the potential for attraction of different suites of floral visitors. Multiple origins of polyploidy also presents the opportunity for new or different plant-insect interactions among independent polyploid lineages. These differences in turn may affect patterns of gene flow between diploids and polyploids and also among plants of independent polyploid origin. Polyploidy, therefore, may result in a geographic mosaic of interspecific interactions across a species' range, contributing to diversification in both plant and insect groups.

8.
J Sex Marital Ther ; 24(1): 43-54, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9509380

RESUMEN

The use of yohimbine to treat impotence has suggested that decreased male sexual desire may relate to decreased activity of central noradrenergic neurons. Previous trials of yohimbine to treat female sexual problems are not available. Yohimbine is an alpha 2-adrenergic antagonist that stimulates norepinephrine (NE) release. In the present study, plasma concentrations of 3-methoxy-4-hydroxyphenylglycol (MHPG), the major central nervous system metabolite of NE, were measured in 9 women diagnosed with hypoactive sexual desire. Daily logs of mood and sexual activity, and trimonthly MHPG blood drawings, were obtained over an initial baseline menstrual cycle followed by two subsequent treatment cycles (yohimbine or placebo), in randomized order. Blood samples were obtained at 9:00 a.m. during (a) the early follicular phase of each cycle (24 hr after the onset of each cycle), (b) the ovulatory phase (i.e., within 1 day of an oral temperature rise), and (c) the midluteal phase (i.e., 20-25 days into each cycle). Comparisons were made with a group of 7 healthy female controls. Women with hypoactive sexual desire had slightly lower plasma MHPG values than controls at baseline, although there was only a trend toward significance during the early follicular phase (p = .09). Yohimbine (5.4 mg orally, 3 times daily, beginning at menses) caused a sustained rise in plasma MHPG of similar magnitude to that reported in men. However, in terms of improved sexual desire, yohimbine had no obvious therapeutic effect. Thus, plasma MHPG and the alpha 2-adrenergic response to yohimbine appeared within normal ranges in women with hypoactive sexual desire, with no therapeutic response to yohimbine.


Asunto(s)
Antagonistas Adrenérgicos alfa/sangre , Antagonistas Adrenérgicos alfa/uso terapéutico , Metoxihidroxifenilglicol/sangre , Metoxihidroxifenilglicol/metabolismo , Disfunciones Sexuales Psicológicas/tratamiento farmacológico , Yohimbina/sangre , Yohimbina/uso terapéutico , Adulto , Cromatografía Líquida de Alta Presión/métodos , Electroquímica/métodos , Femenino , Humanos , Masculino , Ciclo Menstrual/efectos de los fármacos , Persona de Mediana Edad , Norepinefrina/metabolismo , Resultado del Tratamiento
9.
Am Nat ; 150(6): 730-43, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18811333

RESUMEN

We used flow cytometry and extensive geographic surveys of herbivore attack to test whether repeated evolution of autotetraploidy in the perennial herb Heuchera grossulariifolia Rydb. (Saxifragaceae) has created evolutionary barriers to attack by the specialist moth herbivore Greya politella (Prodoxidae). We found that the moth has colonized tetraploid as well as diploid populations, has colonized tetraploids of separate evolutionary origin, and, at least under some conditions, is more likely to attack tetraploids than diploids. Plant polyploidy therefore provides a potential route out of specialization as an evolutionary dead end in phytophagous insect taxa as well as a potentially important route to subsequent phylogenetic and geographic diversification of plant/insect interactions.

11.
J Sex Marital Ther ; 19(3): 198-200, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8246275

RESUMEN

This study evaluated clomipramine as a possible treatment for premature ejaculation. Twenty patients with premature ejaculation were randomly allocated to treatment with clomipramine or placebo in a double-blind study. Average estimated time to ejaculation after vaginal penetration increased to 6.1 minutes on 25 mg. of clomipramine and to 8.4 minutes on 50 mg. of clomipramine. These estimated times were significantly different from estimated time to ejaculation while on placebo. These findings suggest that low dose clomipramine may be useful in the treatment of premature ejaculation.


Asunto(s)
Clomipramina/uso terapéutico , Eyaculación/efectos de los fármacos , Disfunciones Sexuales Psicológicas/tratamiento farmacológico , Adulto , Clomipramina/efectos adversos , Clomipramina/farmacología , Método Doble Ciego , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Placebos , Resultado del Tratamiento
12.
J Urol ; 145(6): 1174-5, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2033687

RESUMEN

In a double-blind study using physiological recording of penile tumescence, brachial subcutaneous apomorphine hydrochloride injections elicited penile erections in men with psychogenic impotence. This observation is compatible with the hypothesis of central dopaminergic involvement in human penile erection. Since apomorphine is believed to induce erections by its effect on brain monoamine pathways, apomorphine response may have diagnostic use in evaluating the etiology of erectile failure.


Asunto(s)
Apomorfina/farmacología , Disfunción Eréctil/tratamiento farmacológico , Erección Peniana/efectos de los fármacos , Método Doble Ciego , Disfunción Eréctil/etiología , Humanos , Masculino
13.
J Sex Marital Ther ; 17(1): 55-8, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-2072405

RESUMEN

The frequency of hypoactive sexual desire disorder (HSDD) and the frequency of comorbidity of sexual disorders was recorded from a total population of 906 subjects studied in a multisite pharmaceutical study. Sixty-five percent had a primary diagnosis of HSDD, HSDD was far more common in females than male subjects. Males diagnosed with HSDD were significantly older than women diagnosed with HSDD. Approximately, 40% of the subjects with a primary diagnosis of HSDD had second diagnoses of arousal or orgasm disorders.


Asunto(s)
Libido , Disfunciones Sexuales Psicológicas/epidemiología , Estudios Transversales , Disfunción Eréctil/diagnóstico , Disfunción Eréctil/epidemiología , Disfunción Eréctil/psicología , Humanos , Incidencia , Masculino , Ohio/epidemiología , Escalas de Valoración Psiquiátrica , Disfunciones Sexuales Psicológicas/diagnóstico , Disfunciones Sexuales Psicológicas/psicología
14.
Med Law ; 10(5): 477-82, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1791742

RESUMEN

Today health care providers are more likely to experience legal, moral and ethical dilemmas regarding their treatment principles given the climate of health care. Clinical practice in the United States is being affected by many external forces which can affect patient care. Government and insurance companies are attempting to legislate treatment as evidenced by DRG's and reimbursement patterns. Hospital and clinic administrators are pressuring faculty and staff to increase revenue by participating in more income generating activities. Within this milieu of dwindling resources, consumers continue to demand a variety of health care services. A case example of a woman who asked for a psychological intervention to treat a medical condition is presented. This case focuses on the important issue of offering efficacious treatments to informed patients with carefully diagnosed disorders. Whether scientific, ethically-based treatments are being rendered when any of the criteria, efficacious, informed and diagnosed are altered or missing, is open to doubt. This case is presented, not as a model of clinical management, but rather to stimulate discussion and generate ideas on how to better address future situations: (a) Where the patient requests an available treatment for a problem which would not be directly helped by such treatment; (b) how far must a clinician go to insure that informed consent has been reached?; (c) what is the physician's responsibility in providing what a patient wants in the way of treatment?; and (d) conversely, should clinicians provide medical interventions (at the patient's insistence) for psychological problems, for example, provide a penile prosthetic implant to a man whose disorder is clearly psychogenic impotence?


Asunto(s)
Terapias Complementarias , Participación del Paciente , Negativa del Paciente al Tratamiento , Biorretroalimentación Psicológica , Femenino , Humanos , Persona de Mediana Edad , Autonomía Personal , Neoplasias Uterinas/psicología , Neoplasias Uterinas/terapia
15.
J Sex Marital Ther ; 16(4): 208-13, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2079704

RESUMEN

Diagnostic information was examined on 258 men with male erectile disorder in a multi-site study. Of the sample, 78% was diagnosed as having difficulty both in obtaining and maintaining erections; 20% had a secondary or tertiary diagnosis of hypoactive sexual desire disorder. There was minimal evidence that the multi-axial diagnostic system has advantages over the categorical DSM-III-R diagnosis of male erectile disorder.


Asunto(s)
Erección Peniana , Disfunciones Sexuales Fisiológicas/diagnóstico , Adulto , Humanos , Masculino , Persona de Mediana Edad , Orgasmo , Disfunciones Sexuales Fisiológicas/fisiopatología , Disfunciones Sexuales Fisiológicas/psicología
16.
Arch Sex Behav ; 16(2): 125-37, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3592960

RESUMEN

The use of sexual symptomatology to differentiate psychogenic from organogenic impotence was studied. All patients were independently classified based on the evaluation of a minimum of one night of nocturnal penile tumescence recording, a sleep lab technician's rating of penile turgidity of erections, Doppler determination of penile blood flow, determination of serum prolactin and testosterone levels. Three aspects of symptomatology significantly discriminated the criterion groups. The single best predictor was the presence or absence of early morning erections as reported by the patient.


Asunto(s)
Disfunción Eréctil/diagnóstico , Anamnesis , Diagnóstico Diferencial , Disfunción Eréctil/etiología , Humanos , Masculino , Persona de Mediana Edad , Erección Peniana , Pene/irrigación sanguínea
17.
J Psychosom Res ; 30(2): 121-5, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3723444

RESUMEN

Thirty-five survivors of extremity sarcomas being followed in a University-Hospital orthopedic clinic were evaluated for current and lifetime presence of psychiatric disorders. Patients were assessed for cognitive abilities using the Cognitive Capacity Screening Examination and for psychiatric disorders using a structured interview format, the Schedule for Affective Disorders and Schizophrenia-Lifetime version. The criteria for psychiatric disorders were the Research Diagnostic Criteria. Two patients were excluded because of cognitive deficiencies; thirty-three patients (mean age = 37.7 yr) were formally evaluated at a mean time of 2.6 yr following cancer diagnosis and surgery. Forty-five per cent of patients were given the diagnosis of at least one lifetime psychiatric disorder. Fifteen per cent of patients reported a current episode. Affective disorders and alcoholism were the most frequently reported disorders.


Asunto(s)
Extremidades , Trastornos Mentales/psicología , Trastornos Psicofisiológicos/psicología , Sarcoma/psicología , Adaptación Psicológica , Trastornos de Adaptación/psicología , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Escalas de Valoración Psiquiátrica
18.
J Clin Oncol ; 3(10): 1393-9, 1985 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-4045528

RESUMEN

When compared to amputation, limb salvage procedures for extremity sarcomas have been advocated because of potential functional benefits and presumed psychological-outcome advantages. The purpose of this study was to compare psychological outcomes between survivors who underwent either amputation or limb salvage procedures for extremity sarcomas. Fifteen amputees and 20 patients with salvaged limbs (mean age, 37.9 years; range, 15 to 71 years) were evaluated 1 to 5 years after surgery for extremity sarcomas. Demographic and medical information was obtained and cognitive functioning, affect, mood, body image, physical functioning, global psychological adjustment to illness and surgery, and lifetime prevalence of psychiatric disorders before and after surgery were assessed. Two patients were excluded because of the presence of an incapacitating organic mental syndrome. The remaining patients, 14 amputees and 19 patients with salvaged limbs, had a variety of soft-tissue and bone sarcomas. No significant differences were found between the groups in age, sex, marital status, surgically involved extremity, chemotherapy status, and social class at the time of surgery and interviews. There were no significant differences between the groups in scores of cognitive capacity, symptoms, mood, body image changes, global physical functioning, global adjustment to illness and surgery, and lifetime prevalence of psychiatric disorders before or after surgery. Most patients revealed only mild psychological symptoms and 55% demonstrated good to excellent adjustment to their surgeries and diseases. There were no significant differences in measures of psychological outcome for patients with extremity sarcomas who underwent limb salvage procedures compared to those who underwent amputation. A psychological-outcome advantage of limb-salvage surgery compared to amputation has yet to be demonstrated.


Asunto(s)
Amputación Quirúrgica/psicología , Extremidades/cirugía , Sarcoma/cirugía , Adaptación Psicológica , Adolescente , Adulto , Anciano , Trastorno Depresivo/etiología , Humanos , Entrevista Psicológica , Persona de Mediana Edad , Trastornos del Humor/etiología , Pronóstico , Estudios Retrospectivos , Sarcoma/psicología
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