RESUMO
PREMISE: Hybrid gene pools harbor more genetic variation than progenitor populations. Thus, we expect hybrid populations to exhibit more dynamic evolutionary responses to environmental variation. We ask how environmental variation experienced by adapted and transplanted populations influence the success of late-generation hybrid populations during invasion. METHODS: For four generations, 20 wild (Raphanus raphanistrum) and 20 hybrid radish (R. sativus × R. raphanistrum) plant populations evolved under experimentally manipulated moisture conditions (dry, wet, control-sheltered, or control-unsheltered plots; i.e., evolutionary environment) in old fields near Toronto, Canada. We planted advanced-generation wild and hybrid radishes in sheltered plots and exposed them to either an evolutionary or a novel watering environment. To determine how soil moisture would influence invasion success, we compared the phenotype and fecundity of plants grown in these various environments. RESULTS: Hybridization produced larger plants. In wet environments, hybrid seedlings emerged more frequently and expressed higher photosynthetic activity. Low-moisture, novel conditions delayed and reduced seedling emergence frequency. Hybrid plants and those that evolved under relatively wet environments exhibited higher aboveground biomass. Hybrid plants from control-sheltered plots colonizing novel moisture environments were more fecund than comparable wild plants. CONCLUSIONS: Dry environments are less likely than other evolutionary environments to contribute colonists. However, relatively wet locations support the evolution of relatively fecund plants, especially crop-wild hybrid populations. Thus, our results provide a strong mechanistic explanation for variation in the relative success of crop-wild hybrids among study locations and a new standard for studies that assess the risk of crop-wild hybridization events.
Assuntos
Raphanus , Canadá , Fertilidade , Hibridização Genética , FenótipoRESUMO
BACKGROUND: People with type 2 diabetes mellitus (T2DM) often experience mental health symptoms that exacerbate illness and increase mortality risk. Access to psychological support is low in people with T2DM. Detection of depression is variable in primary care and can be further hampered by mental health stigma. Electronic mental health (eMH) programs may provide an accessible, private, nonstigmatizing mental health solution for this group. OBJECTIVE: This study aims to evaluate the efficacy over 12 months of follow-up of an eMH program (myCompass) for improving social and occupational functioning in a community sample of people with T2DM and self-reported mild-to-moderate depressive symptoms. myCompass is a fully automated and self-guided web-based public health program for people with depression or anxiety. The effects of myCompass on depressive symptoms, diabetes-related distress, anxiety symptoms, and self-care behavior were also examined. METHODS: Adults with T2DM and mild-to-moderate depressive symptoms (N=780) were recruited via online advertisements, community organizations, and general practices. Screening, consent, and self-report questionnaires were administered online. Eligible participants were randomized to receive either myCompass (n=391) or an attention control generic health literacy program (Healthy Lifestyles; n=379) for 8 weeks. At baseline and at 3, 6, and 12 months postintervention, participants completed the Work and Social Adjustment Scale, the Patient Health Questionnaire-9 item, the Diabetes Distress Scale, the Generalized Anxiety Disorder Questionnaire-7 item, and items from the Self-Management Profile for Type 2 Diabetes. Glycosylated hemoglobin measurements were obtained at baseline and 6 and 12 months postintervention. RESULTS: A total of 38.9% (304/780) of the trial participants completed all postintervention assessments. myCompass users logged in on an average of 6 times and completed an average of 0.29 modules. Healthy Lifestyles users logged in on an average of 4 times and completed an average of 1.37 modules. At baseline, the mean scores on several outcome measures, including the primary outcome of work and social functioning, were close to the normal range, despite a varied and extensive recruitment process. Intention-to-treat analyses revealed slightly greater improvement at 12 months in work and social functioning for the Healthy Lifestyles group relative to the myCompass group. All participants reported equivalent improvements in depression anxiety, diabetes distress, diabetes self-management, and glycemic control across the trial. CONCLUSIONS: The Healthy Lifestyles group reported higher ratings of social and occupational functioning than the myCompass group, but no differences were observed for any secondary outcome. Although these findings should be interpreted in light of the near-floor symptom scores at baseline, the trial yields important insights into how people with T2DM might be engaged in eMH programs and the challenges of focusing specifically on mental health. Several avenues emerge for continued investigation into how best to deal with the growing mental health burden in adults with T2DM. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry Number (ACTRN) 12615000931572; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=368109&isReview=true.
Assuntos
Diabetes Mellitus Tipo 2/psicologia , Diabetes Mellitus Tipo 2/terapia , Intervenção Baseada em Internet/tendências , Saúde Mental/normas , Saúde Ocupacional/normas , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Fatores de Tempo , Adulto JovemRESUMO
Identification of mental health risk is important for optimising diabetes care in type 2 diabetes mellitus (T2DM). Personality is linked to diabetes health and may assist detection of individuals with T2DM most at risk of chronic mental health difficulties. This study examined the moderator effect of personality factors on changes in psychological distress and functioning in adults with T2DM and mild-to-moderate depressive symptoms across a 12-month period. Data were obtained from participants in a randomised controlled trial of adults with T2DM. Participants completed measures of depression (Patient Health Questionnaire-9), anxiety (General Anxiety Disorder-7), general functioning (Work and Social Adjustment Scale), diabetes distress (Diabetes Distress Scale), and diabetes self-management (Self-Management Profile for Type 2 Diabetes) at baseline, 3-, 6- and 12-months. Glycaemic control (HbA1c) was measured at baseline, 6- and 12-months. Two hundred trial completers agreed to complete a personality inventory (Big Five Inventory). Low neuroticism was linked with reduced depression, anxiety, functional impairment and diabetes distress over the year. High extraversion was associated with decreased anxiety and functional impairment. High conscientiousness was linked to increased healthy eating. No personality trait moderated HbA1c levels. Personality screening may help identify mental health risk and guide medical carer approach in T2DM patients.
Assuntos
Ansiedade/psicologia , Depressão/psicologia , Diabetes Mellitus Tipo 2/psicologia , Personalidade , Angústia Psicológica , Adulto , Extroversão Psicológica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuroticismo , Personalidade/fisiologiaRESUMO
OBJECTIVE: To determine whether routine blood glucose assessment of patients admitted to hospital from emergency departments (EDs) results in higher rates of new diagnoses of diabetes and documentation of follow-up plans. DESIGN, SETTING: Cluster randomised trial in 18 New South Wales public district and tertiary hospitals, 31 May 2011 - 31 December 2012; outcomes follow-up to 31 March 2016. PARTICIPANTS: Patients aged 18 years or more admitted to hospital from EDs. INTERVENTION: Routine blood glucose assessment at control and intervention hospitals; automatic requests for glycated haemoglobin (HbA1c ) assessment and notification of diabetes services about patients at intervention hospitals with blood glucose levels of 14 mmol/L or more. MAIN OUTCOME MEASURE: New diagnoses of diabetes and documented follow-up plans for patients with admission blood glucose levels of 14 mmol/L or more. RESULTS: Blood glucose was measured in 133 837 patients admitted to hospital from an ED. The numbers of new diabetes diagnoses with documented follow-up plans for patients with blood glucose levels of 14 mmol/L or more were similar in intervention (83/506 patients, 16%) and control hospitals (73/278, 26%; adjusted odds ratio [aOR], 0.83; 95% CI 0.42-1.7; P = 0.61), as were new diabetes diagnoses with or without plans (intervention, 157/506, 31%; control, 86/278, 31%; aOR, 1.51; 95% CI, 0.83-2.80; P = 0.18). 30-day re-admission (31% v 22%; aOR, 1.34; 95% CI, 0.86-2.09; P = 0.21) and post-hospital mortality rates (24% v 22%; aOR, 1.07; 95% CI, 0.74-1.55; P = 0.72) were also similar for patients in intervention and control hospitals. CONCLUSION: Glucose and HbA1c screening of patients admitted to hospital from EDs does not alone increase detection of previously unidentified diabetes. Adequate resourcing and effective management pathways for patients with newly detected hyperglycaemia and diabetes are needed. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry, ACTRN12611001007921.
Assuntos
Glicemia/análise , Diabetes Mellitus/diagnóstico , Testes Diagnósticos de Rotina/estatística & dados numéricos , Serviços Médicos de Emergência/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Diabetes Mellitus/epidemiologia , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Hiperglicemia/diagnóstico , Hiperglicemia/epidemiologia , Masculino , Pessoa de Meia-Idade , New South WalesRESUMO
BACKGROUND: Depressive symptoms are common in people with type 2 diabetes mellitus (T2DM). Effective depression treatments exist; however, access to psychological support is characteristically low. Web-based cognitive behavioral therapy (CBT) is accessible, nonstigmatizing, and may help address substantial personal and public health impact of comorbid T2DM and depression. OBJECTIVE: The aim of this study was to evaluate the Web-based CBT program, myCompass, for improving social and occupational functioning in adults with T2DM and mild-to-moderate depressive symptoms. myCompass is a fully automated, self-guided public health treatment program for common mental health problems. The impact of treatment on depressive symptoms, diabetes-related distress, anxiety symptoms, and self-care behavior was also examined. METHODS: Participants with T2DM and mild-to-moderate depressive symptoms (N=780) were recruited online via Google and Facebook advertisements targeting adults with T2DM and via community and general practice settings. Screening, consent, and self-report scales were all self-administered online. Participants were randomized using double-blind computerized block randomization to either myCompass (n=391) for 8 weeks plus a 4-week tailing-off period or an active placebo intervention (n=379). At baseline and postintervention (3 months), participants completed the Work and Social Adjustment Scale, the primary outcome measure. Secondary outcome measures included the Patient Health Questionnaire-9 item, Diabetes Distress Scale, Generalized Anxiety Disorder Questionnaire-7 item, and items from the Self-Management Profile for Type 2 Diabetes. RESULTS: myCompass users logged in an average of 6 times and completed an average of .29 modules. Healthy Lifestyles users logged in an average of 4 times and completed an average of 1.37 modules. At baseline, mean scores on several outcome measures, including the primary outcome of work and social functioning, were near to the normal range, despite an extensive recruitment process. Approximately 61.6% (473/780) of participants completed the postintervention assessment. Intention-to-treat analyses revealed improvement in functioning, depression, anxiety, diabetes distress, and healthy eating over time in both groups. Except for blood glucose monitoring and medication adherence, there were no specific between-group effects. Follow-up analyses suggested the outcomes did not depend on age, morbidity, or treatment engagement. CONCLUSIONS: Improvement in social and occupational functioning and the secondary outcomes was generally no greater for myCompass users than for users of the control program at 3 months postintervention. These findings should be interpreted in light of near-normal mean baseline scores on several variables, the self-selected study sample, and sample attrition. Further attention to factors influencing uptake and engagement with mental health treatments by people with T2DM, and the impact of illness comorbidity on patient conceptualization and experience of mental health symptoms, is essential to reduce the burden of T2DM. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12615000931572; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=368109&isReview=true (Archived by WebCite at http://www.webcitation.org/7850eg8pi).
Assuntos
Terapia Cognitivo-Comportamental/métodos , Depressão/etiologia , Depressão/terapia , Diabetes Mellitus Tipo 2/terapia , Feminino , Humanos , Internet , Masculino , Pessoa de Meia-Idade , Medicina do Trabalho , Avaliação de Resultados em Cuidados de Saúde , Habilidades Sociais , Inquéritos e Questionários , Resultado do TratamentoRESUMO
BACKGROUND: E-mental health (eMH) interventions are now widely available and they have the potential to revolutionize the way that health care is delivered. As most health care is currently delivered by primary care, there is enormous potential for eMH interventions to support, or in some cases substitute, services currently delivered face to face in the community setting. However, randomized trials of eMH interventions have tended to recruit participants using online recruitment methods. Consequently, it is difficult to know whether participants who are recruited online differ from those who attend primary care. OBJECTIVE: This paper aimed to document the experience of recruiting to an eMH trial through primary care and compare the characteristics of participants recruited through this and other recruitment methods. METHODS: Recruitment to the SpringboarD randomized controlled trial was initially focused on general practices in 2 states of Australia. Over 15 months, we employed a comprehensive approach to engaging practice staff and supporting them to recruit patients, including face-to-face site visits, regular contact via telephone and trial newsletters, and development of a Web-based patient registration portal. Nevertheless, it became apparent that these efforts would not yield the required sample size, and we therefore supplemented recruitment through national online advertising and promoted the study through existing networks. Baseline characteristics of participants recruited to the trial through general practice, online, or other sources were compared using the analysis of variance and chi square tests. RESULTS: Between November 2015 and October 2017, 780 people enrolled in SpringboarD, of whom 740 provided information on the recruitment source. Of these, only 24 were recruited through general practice, whereas 520 were recruited online and 196 through existing networks. Key barriers to general practice recruitment included perceived mismatch between trial design and diabetes population, prioritization of acute health issues, and disruptions posed by events at the practice and community level. Participants recruited through the 3 different approaches differed in age, gender, employment status, depressive symptoms, and diabetes distress, with online participants being distinguished from those recruited through general practice or other sources. However, most differences reached only a small effect size and are unlikely to be of clinical importance. CONCLUSIONS: Time, labor, and cost-intensive efforts did not translate into successful recruitment through general practice in this instance, with barriers identified at several different levels. Online recruitment yielded more participants, who were broadly similar to those recruited via general practice.
Assuntos
Depressão/terapia , Diabetes Mellitus Tipo 2/terapia , Saúde Mental/tendências , Telemedicina/métodos , Adolescente , Adulto , Idoso , Feminino , Humanos , Internet , Masculino , Pessoa de Meia-Idade , Atenção Primária à Saúde , Adulto JovemRESUMO
OBJECTIVES: While obesity has been linked with lower quality of life in the general adult population, the prospective effects of present obesity on future quality of life amongst the elderly is unclear. This article investigates the cross-sectional and longitudinal relationships between obesity and aspects of quality of life in community-dwelling older Australians. METHOD: A 2-year longitudinal sample of community dwellers aged 70-90 years at baseline, derived from the Sydney Memory and Ageing Study (MAS), was chosen for the study. Of the 1037 participants in the original MAS sample, a baseline (Wave 1) sample of 926 and a 2-year follow-up (Wave 2) sample of 751 subjects were retained for these analyses. Adiposity was measured using body mass index (BMI) and waist circumference (WC). Quality of life was measured using the Assessment of Quality of Life (6 dimensions) questionnaire (AQoL-6D) as well as the Satisfaction with Life Scale (SWLS). Linear regression and analysis of covariance (ANCOVA) were used to examine linear and non-linear relationships between BMI and WC and measures of health-related quality of life (HRQoL) and satisfaction with life, adjusting for age, sex, education, asthma, osteoporosis, depression, hearing and visual impairment, mild cognitive impairment, physical activity, and general health. Where a non-linear relationship was found, established BMI or WC categories were used in ANCOVA. RESULTS: Greater adiposity was associated with lower HRQoL but not life satisfaction. Regression modelling in cross-sectional analyses showed that higher BMI and greater WC were associated with lower scores for independent living, relationships, and pain (i.e. worse pain) on the AQoL-6D. In planned contrasts within a series of univariate analyses, obese participants scored lower in independent living and relationships, compared to normal weight and overweight participants. Longitudinal analyses found that higher baseline BMI and WC were associated with lower independent living scores at Wave 2. CONCLUSIONS: Obesity is associated with and predicts lower quality of life in elderly adults aged 70-90 years, and the areas most affected are independent living, social relationships, and the experience of pain.
Assuntos
Índice de Massa Corporal , Obesidade/psicologia , Satisfação Pessoal , Qualidade de Vida/psicologia , Circunferência da Cintura/fisiologia , Adiposidade/fisiologia , Idoso , Idoso de 80 Anos ou mais , Austrália , Estudos Transversais , Depressão/psicologia , Exercício Físico/fisiologia , Feminino , Humanos , Vida Independente , Estudos Longitudinais , Masculino , Estudos Prospectivos , Inquéritos e QuestionáriosRESUMO
We conducted three single-day point type 2 diabetes prevalence surveys of all inpatient clinical records in November 2013, 2014 and 2016. The prevalence of diabetes was 19.7-25.3%. The majority (63.4-76%) had type 2 diabetes. Twenty-one percent (n = 21) in 2013, 12% (n = 9) in 2014 and 22.6% (n = 21) in 2016 were diagnosed with diabetes during hospital admission; 41.8% (n = 41) in 2013, 46.7% (n = 35) in 2014 and 51.6% (n = 48) in 2016 required insulin. The high prevalence of diabetes among inpatients mandates active detection and specialist management of diabetes during the admission.
Assuntos
Diabetes Mellitus Tipo 2 , Insulina , Erros de Medicação , Administração dos Cuidados ao Paciente , Austrália/epidemiologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Insulina/administração & dosagem , Insulina/efeitos adversos , Masculino , Erros de Medicação/prevenção & controle , Erros de Medicação/estatística & dados numéricos , Pessoa de Meia-Idade , Avaliação das Necessidades , Administração dos Cuidados ao Paciente/métodos , Administração dos Cuidados ao Paciente/normas , Prevalência , Melhoria de QualidadeRESUMO
BACKGROUND: Diabetes increases morbidity and mortality of lung transplantation. However, the reported prevalence of diabetes varies post-transplantation partly due to lack of detection protocols. AIM: To determine the prevalence of diabetes in patients (i) waitlisted for lung transplant and (ii) early post-transplantation. METHODS: We analysed patients on the St Vincent's Heart Lung database from 1 April 2014 to 30 September 2015 on the waitlist (Study 1) and those transplanted (Study 2). Standard of care required all non-diabetic patients to have an oral glucose tolerance test (modified for patients with cystic fibrosis (CF) to screen for CF-related hyperglycaemia (CFRH) (plasma glucose ≥8.2 mmol/L at 60 or 90 min). RESULTS: Study 1 included 114 patients (32 with CF and 82 without CF). Of 30 CF patients with glycaemic data, 27 (90%) had abnormal glucose metabolism: 18 had diabetes and nine had CFRH. In 50 patients without CF, 20 (40%) had abnormal glucose metabolism: eight had diabetes and 12 had impaired fasting glucose and/or impaired glucose tolerance. Study 2 included 78 transplanted patients (25 with CF and 53 without CF). Fourteen CF patients had pre-existing diabetes and seven had pre-existing CFRH. All but one patient were diagnosed with diabetes post-transplantation. Hence, diabetes prevalence in CF patients post-transplantation was 96%. Among 53 transplanted patients without CF, seven (13%) had abnormal glucose metabolism but 30 (57%) were diagnosed with post-transplant diabetes. CONCLUSION: There is a high prevalence of diabetes in lung transplant patients. Earlier endocrine participation in lung transplant services is likely to lower diabetes-related morbidity and mortality further.
Assuntos
Bases de Dados Factuais/tendências , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Transplante de Pulmão/efeitos adversos , Transplante de Pulmão/tendências , Listas de Espera , Adulto , Idoso , Glicemia/metabolismo , Diabetes Mellitus/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: Young people with type 1 diabetes are at increased risk of mental disorders. Whereas treatment need is high, difficulty recruiting young people with type 1 diabetes into psychosocial studies complicates development, testing and dissemination of these interventions. OBJECTIVE: Interviews with young adults with type 1 diabetes were conducted to examine attitudes towards mental health and mental health research, including barriers and motivators to participation in mental health studies and preferred sources of mental health support. The interviews were audio-taped, transcribed and evaluated via thematic analysis. SETTING AND PARTICIPANTS: Young adults with type 1 diabetes were recruited via social media channels of 3 advocacy organizations. A total of 31 young adults (26 females and 5 males) with an average age of 22 years were interviewed between October 2015 and January 2016. RESULTS: Participants were largely unaware of their increased vulnerability to common mental health problems and knew little about mental health research. Major barriers to participation included perceived stigma and lifestyle issues and low levels of trust in researchers. Opportunities to connect with peers and help others were described as key motivators. Psychological distress was considered normal within the context of diabetes. A need for some level of human contact in receiving psychosocial support was expressed. DISCUSSION AND CONCLUSION: Findings provide valuable insights into the complex dynamics of engaging young adults with type 1 diabetes in mental health studies. Interviewees provided practical suggestions to assist investigation and delivery of psychosocial interventions for this vulnerable group.
Assuntos
Atitude Frente a Saúde , Diabetes Mellitus Tipo 1/psicologia , Transtornos Mentais/psicologia , Motivação , Adulto , Feminino , Humanos , Masculino , Saúde Mental , Pesquisa Qualitativa , Mídias Sociais , Estigma Social , Confiança , Adulto JovemRESUMO
BACKGROUND: Depression is twice as common in diabetes mellitus (DM) as the general population and is associated with adverse health outcomes, but access to evidence-based therapies such as cognitive behavioral therapy (CBT) is limited in routine diabetes care. Past research has shown that generic Internet-based cognitive behavioral therapy (iCBT) is an effective treatment for depression in the general population, but it has never been evaluated in people with comorbid depression and DM. OBJECTIVE: The aim of our study was to examine the efficacy of a generic 6-lesson iCBT delivered over 10 weeks in people with major depressive disorder (MDD) and DM. METHODS: Participants with comorbid MDD and DM (type 1 or 2) were recruited online and randomized to an iCBT program with therapist support provided by phone and email (n=42) or a treatment as usual (TAU, n=49) control group. Outcomes were assessed through Web-based self-report questionnaires and the trial was Web-based with no face-to-face components. Primary outcomes were self-reported depression (patient health questionnaire-9, PHQ-9), diabetes-related distress (problem areas in diabetes, PAID), and self-reported glycemic control (hemoglobin A1c, HbA1c). Secondary outcomes were general distress (Kessler 10-item psychological distress scale, K-10) and disability (short form 12-item, SF-12), generalized anxiety (generalized anxiety disorder 7-item, GAD-7), and somatization (PHQ-15). The iCBT group was assessed at 3 months. RESULTS: A total of 27 participants (66%; 27/41) completed the iCBT program. Analyses indicated between-group superiority of iCBT over TAU at posttreatment on PHQ-9 (g=0.78), PAID (g=0.80), K-10 (g=1.06), GAD-7 (g=0.72), and SF-12 mental well-being scores (g=0.66), but no significant differences in self-reported HbA1c levels (g=0.14), SF-12 physical well-being, or PHQ-15 scores (g=0.03-0.21). Gains were maintained at 3-month follow-up in the iCBT group, and the 87% (27/31) of iCBT participants who were interviewed no longer met criteria for MDD. Clinically significant change following iCBT on PHQ-9 scores was 51% (21/41) versus 18% (9/49) in TAU. CONCLUSIONS: iCBT for depression is an efficacious, accessible treatment option for people with diabetes. Future studies should explore whether tailoring of iCBT programs improves acceptability and adherence, and evaluate the long-term outcomes following iCBT. TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry (ACTRN): 12613001198718; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=365208&isReview=true (Archived by WebCite at http://www.webcitation.org/6qCR8Fi9V).
Assuntos
Terapia Cognitivo-Comportamental/métodos , Computadores/estatística & dados numéricos , Depressão/terapia , Internet/estatística & dados numéricos , Adulto , Idoso , Diabetes Mellitus Tipo 1 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: As global climate change transforms average temperature and rainfall, species distributions may meet, increasing the potential for hybridization and altering individual fitness and population growth. Altered rainfall specifically may shift the strength and direction of selection, also manipulating population trajectories. Here, we investigated the role of interspecific hybridization and selection imposed by rainfall on the evolution of weedy life-history in non-hybrid (Raphanus raphanistrum) and hybrid (R. raphanistrum x R. sativus) populations using a life table response experiment. RESULTS: In documenting long-term population dynamics, we determined intrinsic (r) and asymptotic (λ) population growth rates and sensitivities, a measure of selection imposed on demographic rates. Hybrid populations experienced 8.7-10.3 times stronger selection than wild populations for increased seedling survival. Whereas crop populations generally exhibit little dormancy and wild populations often exhibit dormancy, non-hybrid populations experienced 10% stronger selection than hybrid populations for exhibiting seed dormancy. Selection on survival-to-flowering in wild, not hybrid, populations declined marginally with increasing soil moisture. Hybrid populations exhibited greater r, but not λ, than wild populations regardless of moisture environment. In general, fecundity contributed most to differences in λ but fecundity only contributed positively to hybrid λ relative to wild λ when precipitation was altered (either higher or lower than control) and not under control watering conditions. CONCLUSIONS: Selection on key demographic traits may not change dramatically in response to rainfall, and hybridization may more strongly influence the demography of these weedy species than rainfall. If hybrid populations can respond to selection for increased dormancy, this may make it more difficult to deplete weed seed banks and increase the persistence of crop genes in weed populations.
Assuntos
Raphanus/genética , Controle de Plantas Daninhas , Evolução Biológica , Canadá , Mudança Climática , Fertilidade , Hibridização Genética , Plantas Daninhas/genética , Plantas Daninhas/crescimento & desenvolvimento , Chuva , Raphanus/crescimento & desenvolvimento , ReproduçãoAssuntos
Diabetes Mellitus , Insulina , Humanos , Pacientes Internados , Erros de Medicação , PrevalênciaRESUMO
CONTEXT: Individuals with Prader-Willi syndrome (PWS) have a high cardiovascular risk, the mechanism of which is unclear. There may be dysfunction in the autonomic nervous system (ANS) in PWS. OBJECTIVE: To measure, as indicators of cardiac autonomic function, postprandial heart rate variability (HRV) and arterial stiffness in adults with PWS. METHODS: Ten adults with PWS were compared with 11 matched healthy obese subjects and 9 healthy lean subjects. Electrocardiographic traces and arterial stiffness were recorded over a period of 10 minutes at -60, 0, 30, 60, 120 and 240 minutes after consumption of a standardized 600-kCal breakfast. Frequency domain analysis was performed using fast Fourier transform to estimate power spectral density in the full spectrum and in low-frequency (LF 0·04-0·15 Hz) and high-frequency (HF 0·15-0·40 Hz) bands. RESULTS: ANCOVA revealed a reduced LF HRV meal response in adults with PWS compared with obese controls, with no differences in HF HRV, LF/HF ratio, heart rate, total power or arterial stiffness meal responses. CONCLUSIONS: This study assessed cardiac autonomic function in adults with PWS compared with matched obese and lean subjects in response to a meal. Results suggest impaired postprandial ANS responsiveness in PWS, which could contribute to both the known increased cardiovascular risk and obesity.
Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Coração/fisiopatologia , Obesidade/fisiopatologia , Período Pós-Prandial/fisiologia , Síndrome de Prader-Willi/fisiopatologia , Adulto , Análise de Variância , Glicemia/metabolismo , Composição Corporal , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/fisiopatologia , Eletrocardiografia , Feminino , Coração/inervação , Frequência Cardíaca/fisiologia , Humanos , Insulina/sangue , Masculino , Síndrome de Prader-Willi/sangue , Fatores de Risco , Rigidez Vascular/fisiologiaRESUMO
INTRODUCTION: Distress and depression are commonly reported negative affects in people with diabetes (PWD), and may influence glycemic control. 'Distress' can be measured as general or diabetes-related. 'Depression' is considered through symptom severity or episodes of depressive disorder, both potentially derived by the Patient Health Questionnaire (PHQ-9). While current depressive disorder is found to affect the course of diabetes mellitus (DM), past depressive disorder may have a similar impact. OBJECTIVES: To test the relationships between DM-distress (measured by the Problem Areas in Diabetes instrument [PAID]) and glycemic control, while considering the effects of general distress; depression severity; and both current and previous depressive disorder. METHODS: In a diabetic service, 184 type 1 (n = 51) and type 2 (n = 133) PWD completed the PAID, PHQ-9 depression scale from the Patient Health Questionnaire, Kessler-10 psychological distress (K10), and Short-Form Survey (SF-12) instruments. Glycosylated hemoglobin (HbA1c) levels measured on the day of recruitment were recorded from the case notes. RESULTS: DM-related distress correlated positively with HbA1c, PHQ-9 depression, K10, and SF-12 MCS (mental component summary) scores, (all p < 0.01); and negatively with age (p < 0.01). Regression analysis revealed a significant association between PAID with PHQ-9 depression scores (p < 0.01) and with HbA1c (p < 0.01). PWD with past depressive disorder had higher PAID scores than those without (p < 0.05), and this was significant even after controlling for current depression scores (p < 0.05). CONCLUSIONS: In PWD, DM-specific distress measured by the PAID correlated significantly with impaired glycemic control. Both past and current depressions are independently associated with DM-distress. The PAID is discussed as a potential screening tool.
Assuntos
Transtorno Depressivo/psicologia , Diabetes Mellitus/psicologia , Estresse Psicológico/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Diabetes Mellitus/tratamento farmacológico , Feminino , Hemoglobinas Glicadas/análise , Humanos , Hipoglicemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Estresse Psicológico/psicologia , Inquéritos e Questionários , Resultado do Tratamento , Adulto JovemRESUMO
Cannabis sativa L. is cultivated globally for its cannabinoid-dense inflorescences. Commercial preference for sinsemilla has led to the development of methods for producing feminized seeds through cross-pollination of cosexual (masculinized) female plants. Although the induction of cosexuality in Cannabis plants is common, to date, no work has empirically tested how masculinization of female Cannabis plants impacts male flowering, pollen production, pollen fitness, and related life-history trade-offs. Here, we cultivated a population of Cannabis plants (CFX-2) and explored how the route to cosexuality (drought vs. chemical induction) impacted flowering phenology, pollen production, and pollen fitness, relative to unsexual male plants. Unisexual males flowered earlier and longer than cosexual plants and produced 223% more total pollen (F2,28 = 74.41, p < 0.001), but per-flower pollen production did not differ across reproductive phenotypes (F2,21 = 0.887, p = 0.427). Pollen viability was 200% higher in unisexual males and drought-induced cosexuals (F2,36 = 189.70, p < 0.001). Pollen non-abortion rates only differed in a marginally significant way across reproductive phenotypes (F2,36 = 3.00, p = 0.06). Here, we demonstrate that masculinization of female plants impacts whole-plant pollen production and pollen fitness in Cannabis sativa.
RESUMO
Hybridization is hypothesized to promote invasiveness, but empirical tests comparing the performance of hybrid taxa versus parental taxa in novel regions are lacking. We experimentally compared colonization ability of populations of wild radish (Raphanus raphanistrum) with populations of advanced-generation hybrids between wild radish and cultivated radish (Raphanus sativus) in a southeast Texas pasture, well beyond the known invasive range of hybrid radish. We also manipulated the strength of interspecific competition to better generalize across variable environments. In both competitive environments, hybrid populations produced at least three times more seeds than did wild radish populations, a distinction that was driven by greater hybrid seedling emergence, earlier hybrid emergence, and more hybrid seedlings surviving to flower, rather than by greater individual fecundity. Flowering duration in hybrids was less negatively affected by competition than it was in wild radish, while early emergence was associated with subsequent high seed output in both biotypes. Our data show that hybridization can enhance colonization success in a novel region and, by comparison with previous studies, that the life-history traits enhancing hybrid success can differ across regions, even for lineages originating from the same hybridization event. These results imply a much larger arena for hybrid success than previously appreciated.
Assuntos
Quimera/crescimento & desenvolvimento , Produtos Agrícolas/crescimento & desenvolvimento , Hibridização Genética , Raphanus/crescimento & desenvolvimento , Quimera/genética , Quimera/fisiologia , Produtos Agrícolas/genética , Produtos Agrícolas/fisiologia , Michigan , Dinâmica Populacional , Distribuição Aleatória , Raphanus/genética , Raphanus/fisiologia , Reprodução , Especificidade da Espécie , TexasRESUMO
Pollen grains are male gametophytes, an ephemeral haploid generation of plants, that commonly engage in competition for a limited supply of ovules. Since variation in reproductive capabilities among male gametophytes may influence the direction and pace of evolution in populations, we must be able to quantify the relative fitness of gametophytes from different sires. To explore this, we estimated the relative fitness of groups of male gametophytes in a dioecious, wind-pollinated model system, Cannabis sativa, by characterizing the non-abortion rate (measured via chemical staining) and viability (measured via in vitro germination) of pollen from multiple sires. Pollen viability quickly declined within two weeks of anther dehiscence, and pollen stored under freezer conditions did not germinate regardless of storage time. In contrast, pollen non-abortion rates declined slowly and persisted longer than the lifetime of a sporophyte plant under both room temperature and freezer conditions. Pollen samples that underwent both viability and non-abortion rate analysis displayed no significant correlation, implying that researchers cannot predict pollen viability from non-abortion rates, nor infer male gametophytic fitness from a single measure. Our work demonstrates two independent, differential approaches to measure proxies of male fitness in C. sativa.