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1.
Diabetes Res Clin Pract ; 155: 107814, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31421138

RESUMO

INTRODUCTION: Emerging evidence suggests us of real-time continuous glucose monitoring systems (RT-CGM), can assist to improve glucose control in Type 2 Diabetes (T2D) treatment, however the impact of these devices on patients' stress levels and behaviour is poorly understood. This study aimed to examine the effects of RT-CGM on tolerance and acceptability of device wear, stress and diabetes management and motivation to change. METHODS: Twenty adults (10 men, 10 women) with T2D (aged 60.6 ±â€¯8.4 years, BMI 34.2 ±â€¯4.7 kg/m2), were randomised to a low-carbohydrate lifestyle plan whilst wearing a RT-CGM or an 'offline-blinded' (Blinded-CGM) monitoring system continuously for 12 weeks. Outcomes were glycaemic control (HbA1c), weight (kg) perceived stress scale (PSS), CGM device intolerance, acceptability, motivation to change and diabetes management behaviour questionnaires. RESULTS: Both groups experienced significant reductions in body weight (RT-CGM -7.4 ±â€¯4.5 kg vs. Blinded-CGM -5.5 ±â€¯4.0 kg) and HbA1c (-0.67 ±â€¯0.82% vs. -0.68 ±â€¯0.74%). There were no differences between groups for perceived stress (P = 0.47) or device intolerance at week 6 or 12 (both P > 0.30). However, there was evidence of greater acceptance of CGM in the RT-CGM group at week 12 (P = 0.03), improved blood glucose monitoring behaviour in the RT-CGM group at week 6 and week 12 (P ≤ 0.01), and a significant time x group interaction (P = 0.03) demonstrating improved diabetes self-management behaviours in RT-CGM. CONCLUSION: This study provides preliminary evidence of improved behaviours that accompany RT-CGM in the context of diabetes management and glucose self-monitoring. RT-CGM may provide an alternative approach to glucose management in individuals with T2D without resulting in increased disease distress.


Assuntos
Automonitorização da Glicemia/métodos , Diabetes Mellitus Tipo 2/sangue , Estilo de Vida Saudável/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
2.
Phys Rev Lett ; 121(9): 097701, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-30230891

RESUMO

We report on the fabrication of Josephson junctions using the topological crystalline insulator Pb_{0.5}Sn_{0.5}Te as the weak link. The properties of these junctions are characterized and compared to those fabricated with weak links of PbTe, a similar material yet topologically trivial. Most striking is the difference in the ac Josephson effect: junctions made with Pb_{0.5}Sn_{0.5}Te exhibit a rich subharmonic structure consistent with a skewed current-phase relation. This structure is absent in junctions fabricated from PbTe. A discussion is given on the origin of this effect as an indication of novel behavior arising from the topologically nontrivial surface state.

3.
J Sports Sci ; 34(11): 1094-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26367197

RESUMO

Running economy is a reflection of the amount of inspired oxygen required to maintain a given velocity and is considered a determining factor for running performance. Athletic footwear has been advocated as a mechanism by which running economy can be enhanced. New commercially available footwear has been developed in order to increase energy return, although their efficacy has not been investigated. This study aimed to examine the effects of energy return footwear on running economy in relation to conventional running shoes. Twelve male runners completed 6-min steady-state runs in conventional and energy return footwear. Overall, oxygen consumption (VO2), heart rate, respiratory exchange ratio, shoe comfort and rating of perceived exertion were assessed. Moreover, participants subjectively indicated which shoe condition they preferred for running. Differences in shoe comfort and physiological parameters were examined using Wilcoxon signed-rank tests, whilst shoe preferences were tested using a chi-square analysis. The results showed that VO2 and respiratory exchange ratio were significantly lower, and shoe comfort was significantly greater, in the energy return footwear. Given the relationship between running economy and running performance, these observations indicate that the energy return footwear may be associated with enhanced running performance in comparison to conventional shoes.


Assuntos
Desempenho Atlético/fisiologia , Consumo de Oxigênio , Corrida/fisiologia , Sapatos , Fenômenos Biomecânicos , Frequência Cardíaca , Humanos , Masculino , Adulto Jovem
4.
Psychol Med ; 45(13): 2849-59, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25990802

RESUMO

BACKGROUND: Extensive evidence has shown that experiencing a traumatic event and post-traumatic stress disorder (PTSD) are associated with experiences of psychosis. However, less is known about specific PTSD symptoms and their relationship with psychotic experiences. This study aimed to examine the relationship between symptoms of PTSD with paranoia and auditory hallucinations in a large-scale sample. METHOD: The Adult Psychiatric Morbidity Survey (APMS) was utilized to examine the prevalence of lifetime trauma, symptoms of PTSD, and experiences of paranoia and auditory hallucinations (n = 7403). RESULTS: There were significant bivariate associations between symptoms of PTSD and psychotic experiences. Multiple logistic regression analyses indicated that reliving and arousal symptoms were significant predictors for paranoia while reliving, but not arousal symptoms, also significantly predicted auditory hallucinations. A dose-response relationship was found, the greater the number of PTSD symptoms, the greater the odds were of experiencing both paranoia and hallucinations. CONCLUSIONS: These findings illustrate that symptoms of PTSD are associated with increased odds of experiencing auditory hallucinations and paranoia. Overlaps appear to be present between the symptoms of PTSD and psychotic experiences. Increasing awareness of this association may advance work in clinical practice.


Assuntos
Alucinações/epidemiologia , Transtornos Paranoides/epidemiologia , Transtornos Psicóticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/complicações , Adolescente , Adulto , Idoso , Feminino , Humanos , Modelos Logísticos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Razão de Chances , Transtornos Psicóticos/terapia , Fatores de Risco , Transtornos de Estresse Pós-Traumáticos/terapia , Inquéritos e Questionários , Adulto Jovem
5.
Psychol Med ; 45(5): 911-26, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25298008

RESUMO

BACKGROUND: Suicide and self-harm are prevalent in individuals diagnosed with psychotic disorders. However, less is known about the level of self-injurious thinking and behaviour in those individuals deemed to be at ultra-high risk (UHR) of developing psychosis, despite growing clinical interest in this population. This review provides a synthesis of the extant literature concerning the prevalence of self-harm and suicidality in the UHR population, and the predictors and correlates associated with these events. METHOD: A search of electronic databases was undertaken by two independent reviewers. A meta-analysis of prevalence was undertaken for self-harm, suicidal ideation and behaviour. A narrative review was also undertaken of analyses examining predictors and correlates of self-harm and suicidality. RESULTS: Twenty-one eligible studies were identified. The meta-analyses suggested a high prevalence of recent suicidal ideation (66%), lifetime self-harm (49%) and lifetime suicide attempts (18%). Co-morbid psychiatric problems, mood variability and a family history of psychiatric problems were among the factors associated with self-harm and suicide risk. CONCLUSIONS: Results suggest that self-harm and suicidality are highly prevalent in the UHR population, with rates similar to those observed in samples with diagnosed psychotic disorders. Appropriate monitoring and managing of suicide risk will be important for services working with the UHR population. Further research in this area is urgently needed considering the high rates identified.


Assuntos
Transtornos Psicóticos/epidemiologia , Risco , Ideação Suicida , Tentativa de Suicídio/estatística & dados numéricos , Suicídio/estatística & dados numéricos , Humanos , Prevalência , Comportamento Autodestrutivo/epidemiologia
6.
J R Army Med Corps ; 161(2): 140-3, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25428136

RESUMO

Military recruits are known to be susceptible to Achilles tendon pathology. The British Army have introduced footwear models, the PT-03 (cross-trainer) and PT1000 (running shoes), in an attempt to reduce the incidence of injuries. The aim of the current investigation was to examine the Achilles tendon forces of the cross-trainer and running shoe in relation to conventional army boots. Ten male participants ran at 4.0 m/s in each footwear condition. Achilles tendon forces were obtained throughout the stance phase of running and compared using repeated-measures ANOVAs. The results showed that the time to peak Achilles tendon force was significantly shorter when running in conventional army boots (0.12 s) in comparison with the cross-trainer (0.13 s) and running shoe (0.13 s). Achilles tendon loading rate was shown to be significantly greater in conventional army boots (38.73 BW/s) in comparison with the cross-trainer (35.14 BW/s) and running shoe (33.57 BW/s). The results of this study suggest that the running shoes and cross-trainer footwear are associated with reductions in Achilles tendon parameters that have been linked to the aetiology of injury, and thus it can be hypothesised that these footwear could be beneficial for military recruits undertaking running exercises.


Assuntos
Tendão do Calcâneo/fisiologia , Corrida/fisiologia , Sapatos , Adulto , Fenômenos Biomecânicos , Humanos , Masculino , Militares , Adulto Jovem
7.
J Sports Sci ; 32(20): 1914-1923, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25333601

RESUMO

Abstract The current investigation aimed to determine whether there are differences in ball velocity and 3D kinematics when performing maximal kicks with the dominant and non-dominant limbs. Seventeen male academy soccer players performed maximal speed place kicks with their dominant and the non-dominant limbs. The 3D kinematics of the lower extremities were obtained using a 10-camera motion capture system operating at 500 Hz. Hip, knee and ankle joint kinematics were quantified in the sagittal, coronal and transverse planes and then contrasted using paired t-tests. Significantly higher ball velocities were obtained with the dominant limb. Foot linear velocity and knee extension velocity at ball contact were also found to be significantly greater in the dominant limb. That reduced ball velocities were observed between kicking limbs highlights the potential performance detriments that may occur when kicking with the non-dominant limb; thus, it is recommended that additional bilateral training be undertaken in order to attenuate this and improve overall kicking performance.

8.
Clin Biomech (Bristol, Avon) ; 29(8): 956-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25146855

RESUMO

BACKGROUND: Achilles tendon pathology is a frequently occurring musculoskeletal disorder in runners. Foot orthoses have been shown to reduce the symptoms of pain in runners but their mechanical effects are still not well understood. METHODS: This study aimed to examine differences in Achilles tendon load when running with and without orthotic intervention. Twelve male runners ran at 4.0 m·s(-1). Ankle joint moments and Achilles tendon forces were compared when running with and without orthotics. FINDINGS: The results indicate that running with foot orthotics was associated with significant reductions in Achilles tendon load compared to without orthotics. INTERPRETATION: In addition to providing insight into the mechanical effects of orthotics in runners, the current investigation suggests that via reductions in Achilles tendon load, foot orthoses may serve to reduce the incidence of chronic Achilles tendon pathologies in runners.


Assuntos
Tendão do Calcâneo/fisiopatologia , Articulação do Tornozelo/fisiopatologia , Órtoses do Pé , Pé/fisiopatologia , Corrida/fisiologia , Adulto , Atletas , Traumatismos em Atletas , Fenômenos Biomecânicos , Humanos , Masculino , Doenças Musculoesqueléticas/fisiopatologia , Adulto Jovem
9.
Gait Posture ; 40(4): 707-11, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25022594

RESUMO

The efficacy of 3D motion capture in both sports and clinical research settings is largely dependent on the reliability of the obtained measurements. This study aimed to determine whether there are 3D kinematic differences both between and within researchers with three different levels of familiarity in 3D marker placement. Fifteen male participants ran across a 22 m laboratory at 4.0 m.s(-1). Three researchers (experienced, intermediate and novice) positioned lower extremity markers on two occasions. Differences in 3D joint kinetics/kinematics both between and within researchers were examined using mixed ANOVA's. The within researcher reliability of the kinetic/kinematic waveforms were further analysed using intraclass correlations. The results show that significant differences in discrete parameters were observed in the transverse plane between researchers and also in the coronal and transverse planes within researcher for the novice practitioner. Furthermore, the results also showed that the experienced researcher was associated with the highest levels of reliability in marker placement. This suggests that it may be prudent for 3D analyses, in particular those with a clinical component to be conducted using experienced practitioners and for analyses to state the experience level of the researchers conducting the anatomical marker placement.


Assuntos
Extremidade Inferior/fisiologia , Monitorização Ambulatorial/normas , Competência Profissional , Corrida/fisiologia , Adulto , Fenômenos Biomecânicos , Humanos , Masculino , Reprodutibilidade dos Testes
10.
Gait Posture ; 40(3): 476-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24909580

RESUMO

The examination of synchronous three dimensional (3-D) kinetics and kinematics of walking in laboratory based analyses typically requires participants/patients to make foot contact with a force or pressure measuring device. However, it has been proposed that this may lead to targeting whereby participants modify their natural gait pattern in order to ensure contact with the device. This study aimed to determine the extent to which an embedded force plate (EFP) and two different pressure mats (PMs) affect natural gait kinematics. Male participants (n = 12, age 24.23 SD 4.22 years, height 1.74 m SD 0.10, mass 75.78 SD 6.90 kg) walked at a velocity of 1.25 ms(-1) along a 22 m walkway in four different conditions. (1) EFP, (2) FootScan (FS) PM, (3) MatScan (MS) PM, (4) no device (ND). 3-D angular kinematic parameters were collected using an eight camera motion analysis system. Differences in kinematics were examined using repeated measures ANOVAs. Significant differences were observed in hip abduction, knee flexion/extension and knee abduction between various conditions and may warrant consideration in future research. No significant differences were reported at the ankle joint in any conditions. Comparing the PMs, no significant differences were observed, however, significant differences between the MS and the EFP and ND conditions were identified. The research supports the efficacy of collecting gait kinematics at the ankle joint and in most variables measured at the knee and hip joints.


Assuntos
Extremidade Inferior/fisiologia , Transdutores , Caminhada/fisiologia , Adulto , Articulação do Tornozelo/fisiologia , Fenômenos Biomecânicos , Articulações do Pé/fisiologia , Marcha/fisiologia , Voluntários Saudáveis , Articulação do Quadril/fisiologia , Humanos , Articulação do Joelho/fisiologia , Masculino , Monitorização Ambulatorial/instrumentação , Pressão , Amplitude de Movimento Articular/fisiologia , Rotação
11.
Psychol Med ; 44(3): 449-68, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23521867

RESUMO

BACKGROUND: Clinical equipoise regarding preventative treatments for psychosis has encouraged the development and evaluation of psychosocial treatments, such as cognitive behavioural therapy (CBT). METHOD: A systematic review and meta-analysis was conducted, examining the evidence for the effectiveness of CBT-informed treatment for preventing psychosis in people who are not taking antipsychotic medication, when compared to usual or non-specific control treatment. Included studies had to meet basic quality criteria, such as concealed and random allocation to treatment groups. RESULTS: Our search produced 1940 titles, out of which we found seven completed trials (six published). The relative risk (RR) of developing psychosis was reduced by more than 50% for those receiving CBT at every time point [RR at 6 months 0.47, 95% confidence interval (CI) 0.27-0.82, p = 0.008 (fixed-effects only: six randomized controlled trials (RCTs), n = 800); RR at 12 months 0.45, 95% CI 0.28-0.73, p = 0.001 (six RCTs, n = 800); RR at 18-24 months 0.41, 95% CI 0.23-0.72, p = 0.002 (four RCTs, n = 452)]. Heterogeneity was low in every analysis and the results were largely robust to the risk of an unpublished 12-month study having unfavourable results. CBT was also associated with reduced subthreshold symptoms at 12 months, but not at 6 or 18-24 months. No effects on functioning, symptom-related distress or quality of life were observed. CBT was not associated with increased rates of clinical depression or social anxiety (two studies). CONCLUSIONS: CBT-informed treatment is associated with a reduced risk of transition to psychosis at 6, 12 and 18-24 months, and reduced symptoms at 12 months. Methodological limitations and recommendations for trial reporting are discussed.


Assuntos
Terapia Cognitivo-Comportamental , Sintomas Prodrômicos , Transtornos Psicóticos/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Transtornos de Ansiedade/epidemiologia , Viés , Transtorno Depressivo/epidemiologia , Progressão da Doença , Humanos , Números Necessários para Tratar , Transtornos Psicóticos/epidemiologia , Transtornos Psicóticos/psicologia , Qualidade de Vida , Risco , Ajustamento Social , Equipolência Terapêutica , Fatores de Tempo , Resultado do Tratamento
12.
Compr Psychiatry ; 55(1): 104-12, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23972619

RESUMO

BACKGROUND: A growing body of research has highlighted the importance of identifying resilience factors against suicidal behavior. However, no previous study has investigated potential resilience factors among individuals with Posttraumatic Stress Disorder (PTSD). The aim of this study was to examine whether perceived social support buffered the impact of PTSD symptoms on suicidal behavior. METHODS: Fifty-six individuals who had previously been exposed to a traumatic event and reported PTSD symptoms in the past month (n = 34, 60.7% participants met the full criteria for a current PTSD diagnosis) completed a range of self-report measures assessing PTSD symptoms, perceived social support and suicidal behavior. Hierarchical regression analyses were conducted to examine whether perceived social support moderates the effects of PTSD symptoms on suicidal behavior. RESULTS: The results showed that perceived social support moderated the impact of the number and severity of PTSD symptoms on suicidal behavior. For those who perceived themselves as having high levels of social support, an increased number and severity of PTSD symptoms were less likely to lead to suicidal behavior. CONCLUSIONS: The current findings suggest that perceived social support might confer resilience to individuals with PTSD and counter the development of suicidal thoughts and behaviors. The milieu of social support potentially provides an area of further research and an important aspect to incorporate into clinical interventions for suicidal behavior in PTSD or trauma populations.


Assuntos
Resiliência Psicológica , Apoio Social , Transtornos de Estresse Pós-Traumáticos/psicologia , Ideação Suicida , Tentativa de Suicídio/psicologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Índice de Gravidade de Doença
13.
Sports Biomech ; 11(3): 430-7, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23072052

RESUMO

Cardan/Euler and helical angles are the popular methods of quantifying angular kinematics. Cardan angles are sequence dependent and crosstalk can influence the kinematic calculations. The International Society of Biomechanics (ISB) recommends a sagittal, coronal, and then transverse (XYZ) sequence of rotations, although it has been proposed that when calculating rotations outside of the sagittal plane, this may not be the most appropriate method. This study investigated the influence of the helical and six available Cardan sequences on three-dimensional (3D) ankle joint kinematics. Kinematic data were obtained using an eight-camera motion analysis system as participants ran at 4.0 m/s +/- 5%. Repeated measures ANOVAs were used to compare kinematic parameters, and intraclass correlations were employed to identify evidence of crosstalk across planes. The results indicate that in the transverse and coronal planes, peak angle and range of motion values using the YXZ and ZXY sequences were significantly greater than the other sequences. Furthermore, utilization of YXZ and ZXY sequences was associated with the strongest correlations from the sagittal plane, and the XYZ sequence was found to be associated with the lowest correlations. It appears that for the representation of 3D ankle joint kinematics, the XYZ sequence is associated with minimal planar crosstalk and as such its use is encouraged.


Assuntos
Articulação do Tornozelo/fisiologia , Movimento/fisiologia , Corrida/fisiologia , Adolescente , Análise de Variância , Fenômenos Biomecânicos , Humanos , Imagem Tridimensional , Masculino , Amplitude de Movimento Articular , Rotação , Adulto Jovem
14.
J Affect Disord ; 143(1-3): 5-15, 2012 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-22842024

RESUMO

BACKGROUND: Suicide represents a substantial problem, with significant societal and personal impact. The identification of factors influencing suicide risk is an important step in preventing self-harming behaviour. In this article the authors explore whether emotional instability increases risk of suicide, beyond that of mood intensity. METHOD: This article provides a summary of existing theory and indirect evidence in support of an association between emotional instability and suicidality. A systematic literature search (Embase, Medline, PsychInfo) was carried out on literature conducted up to October, 2011. Meta-analysis was used to assess the strength of the proposed association. RESULTS: The systematic search identified 20 journal articles meeting the inclusion criteria, including retrospective questionnaire design studies and research conducted across several time-points. Meta-analysis revealed a moderate association, which remained statistically significant even when only including studies conducted over multiple time-points. This effect was attenuated, but remained significant, when controlling for study selection bias. LIMITATIONS: Retrospective questionnaire studies failed to adequately control for mood level. Little is still currently understood about the types of emotional instability (e.g., dysoria, anxiety) most associated with suicidality. CONCLUSIONS: Future avenues of investigation include micro- to macro-longitudinal research and the differentiation of emotion subtypes and instability metrics. Momentary assessment techniques may help to detect subtle fluctuations in mood leading to more effective and immediate intervention. Psychosocial intervention strategies for treating unstable emotions are discussed.


Assuntos
Transtornos do Humor/psicologia , Suicídio/psicologia , Ansiedade/psicologia , Transtornos de Ansiedade/psicologia , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
15.
Acta Psychiatr Scand ; 126(1): 1-11, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22486554

RESUMO

OBJECTIVE: Our aim was to find out how Cochrane reviews of five popular or frequently prescribed second-generation antipsychotics in the UK (olanzapine, risperidone, quetiapine, amisulpride and aripiprazole) approached the problem of high drop-out in placebo-controlled trials. METHOD: We examined the following: (i) whether reviews included data from studies with a level of drop-out exceeding their stated exclusion criterion; (ii) the level of missing data each efficacy outcome in each review relied upon; and (iii) impact of excluding studies with high drop-out. RESULTS: All reviews included data they stated they would exclude because of unacceptable levels of attrition, four (risperidone, olanzapine, amisulpride, aripiprazole) without clear acknowledgement or justification. Several reviews also excluded data from a number of relatively low-attrition studies because of missing standard deviations. CONCLUSION: Cochrane reviews of five popular antipsychotics for schizophrenia misrepresented the available evidence on their efficacy. The impact of including high-attrition studies was difficult to quantify because of the exclusion of relevant low-attrition studies. Further analysis of the efficacy of these drugs in studies with acceptable rates of attrition is required. To reduce the problem of high attrition, trialists should gather follow-up data from people who leave the double-blind process early.


Assuntos
Antipsicóticos/uso terapêutico , Pacientes Desistentes do Tratamento/estatística & dados numéricos , Esquizofrenia/tratamento farmacológico , Amissulprida , Aripiprazol , Benzodiazepinas/uso terapêutico , Interpretação Estatística de Dados , Dibenzotiazepinas/uso terapêutico , Humanos , Olanzapina , Piperazinas/uso terapêutico , Fumarato de Quetiapina , Quinolonas/uso terapêutico , Literatura de Revisão como Assunto , Risperidona/uso terapêutico , Sulpirida/análogos & derivados , Sulpirida/uso terapêutico
16.
Br J Clin Psychol ; 51(1): 72-83, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22268542

RESUMO

OBJECTIVE: There is a suggestion in the literature that more variable affect increases suicidal ideation through the repeated re-activation of latent suicidal cognitions. The hypothesis that affective variability would be a better predictor of suicidal ideation and related behaviour than affect level was tested in individuals at ultra-high risk of developing psychosis. This study also examined the prediction that affective variability is a suicide-specific mechanism and would not predict levels of attenuated psychotic phenomena. METHOD: Twenty-seven ultra-high risk individuals were required to complete ambulant ratings of their affect when prompted by an electronic wristwatch for six days (the experience sampling method). In the debriefing session, participants were assessed with a semi-structured interview (the Comprehensive Assessment of At-Risk Mental State), which assessed the severity and frequency of suicidality and psychosis-related phenomena. RESULTS: The variability of negative and positive affect was predictive of the frequency of suicidal thoughts and behaviour. More variable negative, but not positive affect, was also associated with more severe suicidal ideation and related behaviour. Affect variability was not significantly related to the severity of attenuated psychotic phenomena. CONCLUSION: Affective variability appears to be a specific risk factor for suicidal ideation in individuals at ultra-high risk of developing psychosis. Early intervention should focus on providing individuals with skills for regulating their own affect.


Assuntos
Afeto , Transtornos Psicóticos/psicologia , Ideação Suicida , Adulto , Feminino , Humanos , Entrevista Psicológica , Masculino , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Risco , Fatores de Risco , Índice de Gravidade de Doença , Adulto Jovem
17.
Horm Metab Res ; 44(3): 170-6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22147655

RESUMO

Although the aldosterone/renin ratio (ARR) is the most reliable screening test for primary aldo-steronism, false positives and negatives occur. Dietary salt restriction, concomitant malignant or renovascular hypertension, pregnancy and treatment with diuretics (including spironolactone), dihydropyridine calcium blockers, angiotensin converting enzyme inhibitors, and angiotensin receptor antagonists can produce false negatives by stimulating renin. We recently reported selective serotonin reuptake inhibitors lower the ratio. Because potassium regulates aldosterone, uncorrected hypokalemia can lead to false negatives. Beta-blockers, alpha-methyldopa, clonidine, and nonsteroidal anti-inflammatory drugs suppress renin, raising the ARR with potential for false positives. False positives may occur in patients with renal dysfunction or advancing age. We recently showed that (1) females have higher ratios than males, and (2) false positive ratios can occur during the luteal menstrual phase and while taking an oral ethynylestradiol/drospirenone (but not implanted subdermal etonogestrel) contraceptive, but only if calculated using direct renin concentration and not plasma renin activity. Where feasible, diuretics should be ceased at least 6 weeks and other interfering medications at least 2 before ARR measurement, substituting noninterfering agents (e. g., verapamil slow-release±hydralazine and prazosin or doxazosin) were required. Hypokalemia should be corrected and a liberal salt diet encouraged. Collecting blood midmorning from seated patients following 2-4 h upright posture improves sensitivity. The ARR is a screening test only and should be repeated once or more before deciding whether to proceed to confirmatory suppression testing. Liquid chromatography-tandem mass spectrometry aldosterone assays represent a major advance towards addressing inaccuracies inherent in other available methods.


Assuntos
Aldosterona , Testes Diagnósticos de Rotina/normas , Hiperaldosteronismo/diagnóstico , Renina , Aldosterona/sangue , Testes Diagnósticos de Rotina/métodos , Feminino , Humanos , Hiperaldosteronismo/sangue , Masculino , Gravidez , Renina/sangue , Sensibilidade e Especificidade
18.
Cytogenet Genome Res ; 133(1): 8-15, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21228562

RESUMO

Pericentric inversions are important for evolutionary biology because of their potential role in speciation. They may result in reproductive isolation due to illegitimate pairing of homologues at meiosis which leads to the production of aneuploid gametes (containing deletions or duplications of chromosomal segments), and consequently mediate chromosomal divergence. In this study, we describe the prevalence of pericentric inversions in the African vlei rat, Otomys irroratus (OIR). The species is characterized by intraspecific chromosomal variation (2n = 23-32) across its distribution in southern Africa. Here, we analyzed 55 individuals collected from 7 localities in South Africa by G- and C-banding and chromosome painting with flow sorts of Myotomys unisulcatus. Of the 55 specimens that were analyzed, 47% contained inversions or centromeric shifts on 4 autosomes (OIR1, 4, 6 and 10) which were present singly in specimens (i.e. none of the specimens contained all 4 inversions concurrently). These inversions were found in both homozygous and heterozygous state over a wide geographic range suggesting that they are floating polymorphisms. Given the potential role of inversions in post-mating isolation (through production of aneuploid gametes), the prevalence of inversions as floating polymorphisms in the vlei rats suggests that they are probably retained in the population through suppression of recombination in the inverted regions of the chromosomes.


Assuntos
Centrômero , Inversão Cromossômica , Cromossomos de Mamíferos , Diploide , Murinae/genética , Polimorfismo Genético , Animais , Bandeamento Cromossômico , Coloração Cromossômica , Evolução Molecular , África do Sul
19.
Behav Res Ther ; 48(9): 883-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20538264

RESUMO

Recent years have seen growing interest into concepts of resilience, but minimal research has explored resilience to suicide and none has investigated resilience to suicide amongst clinical groups. The current study aimed to examine whether a proposed resilience factor, positive self-appraisals of the ability to cope with emotions, difficult situations and the ability to gain social support, could buffer against the negative impact of hopelessness amongst individuals with psychosis-spectrum disorders when measured cross-sectionally. Seventy-seven participants with schizophrenia-spectrum disorders completed self-report measures of suicidal ideation, hopelessness and positive self-appraisals. Positive self-appraisals were found to moderate the association between hopelessness and suicidal ideation. For those reporting high levels of positive self-appraisals, increased levels of hopelessness were significantly less likely to lead to suicidality. These results provide cross-sectional evidence suggest that positive self-appraisals may buffer individuals with psychosis against the pernicious impact of a well known clinical risk factor, hopelessness. Accounting for positive self-appraisals may improve identification of individuals at high risk of suicidality, and may be an important area to target for suicide interventions.


Assuntos
Psicoterapia/métodos , Transtornos Psicóticos/psicologia , Resiliência Psicológica , Esquizofrenia/terapia , Ideação Suicida , Suicídio/psicologia , Adaptação Psicológica , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Psicóticos/terapia , Psicologia do Esquizofrênico , Autoimagem , Autoavaliação , Suicídio/prevenção & controle
20.
Placenta ; 30(9): 792-9, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19674786

RESUMO

Bats are a highly successful, widely distributed group, with considerable variation in placental structure. The Egyptian slit-faced bat Nycteris thebaica is a member of one of the few families with previously undescribed placentation. It was found that, although the interhemal type of the Nycteris placenta is endotheliochorial with a single layer of cytotrophoblast, the arborizing pattern of the maternal vessels and especially the extraordinary major placental artery differs from the placenta of the emballonurid bats to which this family is considered to be most closely related. The major placental artery providing maternal blood to the vessels of the placental disk has a highly glycosylated matrix surrounded by two-layered folds of trophoblast, forming an apparently rigid structure of unique morphology. The yolk sac is collapsed, with hypertrophied endodermal and mesothelial cells similar to many other bat species. The paraplacenta is extensive with abundant fetal vessels underlying cytotrophoblast and syncytial trophoblast layers, fronting on an endometrium that largely lacks uterine epithelial cells but has large decidual cells and is poorly vascularized. The placenta of Nycteris lacks a hemophagous region, unlike the emballonurid bats Taphozous and Saccopteryx. Although the latter two species have similar placentas, the placental structure of Nycteris does little to relate it to the other family within the Emballonuroidea. Shared and divergent reproductive characters are discussed in relationship to bat phylogenetic relationships.


Assuntos
Quirópteros/fisiologia , Placenta/anatomia & histologia , Placentação/fisiologia , Animais , Eritrócitos/fisiologia , Membranas Extraembrionárias/anatomia & histologia , Feminino , Feto/irrigação sanguínea , Histocitoquímica , Lectinas/metabolismo , Fagocitose , Filogenia , Placenta/irrigação sanguínea , Placenta/metabolismo , Placenta/ultraestrutura , Circulação Placentária , Gravidez , Especificidade da Espécie , Saco Vitelino/anatomia & histologia
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