Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 74
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Int Neuropsychol Soc ; 26(1): 19-30, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31983373

RESUMO

OBJECTIVE: Meta-analyses report moderate effects across cognitive remediation (CR) trials in schizophrenia. However, individual responses are variable, with some participants showing no appreciable gain in cognitive performance. Furthermore, reasons for heterogeneous outcome are undetermined. We examine the extent to which CR outcome is attributable to near learning-direct gains in trained cognitive tasks-while also exploring factors influencing far transfer of gains during training to external cognitive measures. METHOD: Thirty-seven schizophrenia outpatients were classified as CR responders and non-responders according to change in MATRICS Consensus Cognitive Battery composite score following 20 sessions of computer-based training. Metrics of near learning during training, as well as baseline demographic, clinical, cognitive, and electroencephalographic (EEG) measures, were examined as predictors of responder status. RESULTS: Significant post-training improvement in cognitive composite score (Cohen's d = .41) was observed across the sample, with n = 21 and n = 16 classified as responders and non-responders, respectively. Near learning was evidenced by significant improvement on each training exercise with practice; however, learning did not directly predict responder status. Group-wise comparison of responders and non-responders identified two factors favoring responders: higher EEG individual alpha frequency (IAF) and lower antipsychotic dosing. Tested in moderation analyses, IAF interacted with learning to predict improvement in cognitive outcome. CONCLUSION: CR outcome in schizophrenia is not directly explained by learning during training and appears to depend on latent factors influencing far transfer of trained abilities. Further understanding of factors influencing transfer of learning is needed to optimize CR efficacy.

2.
Acta Paediatr ; 107(10): 1759-1765, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29520851

RESUMO

AIM: We investigated children's counter regulatory hormone profiles during a hyperinsulinaemic hypoglycaemic clamp procedure at day and night. METHODS: In 2013, we assessed the counter regulatory response to hypoglycaemia in eight outpatients with type 1 diabetes, recruited from the Herlev Hospital, Denmark, at a mean age of 9.6 ± 2.3 years. Hyperinsulinaemic 80 mU/m2 /min clamps were performed with a stepwise reduction in plasma glucose from euglycaemia (7-9 mmol/L) to hypoglycaemia (<3.5 mmol/L) and the glucose nadir (≤2.2 mmol/L) during the day and night. Adrenaline, cortisol, glucagon and growth hormone levels were assessed. RESULTS: Adrenaline and growth hormone levels were higher during the day versus the night (p = 0.04 and p = 0.01, respectively). However, at the glucose nadir, the level of adrenaline was lower during the night than the day (0.6 ± 0.2 versus 1.9 ± 0.5 nmol/L, p = 0.016) and cortisol was lower during the day than the night (42 ± 15 versus 319 ± 81 nmol/L, p = 0.016). No differences were demonstrated for glucagon and growth hormone levels based on the same criteria. CONCLUSION: The adrenaline response was blunted during nocturnal iatrogenic hypoglycaemia in our study cohort, and no increase in cortisol levels was demonstrated.


Assuntos
Ritmo Circadiano , Diabetes Mellitus Tipo 1/sangue , Epinefrina/sangue , Hidrocortisona/sangue , Hipoglicemia/sangue , Glicemia , Criança , Diabetes Mellitus Tipo 1/tratamento farmacológico , Eletrocardiografia , Feminino , Glucagon/sangue , Técnica Clamp de Glucose , Hormônio do Crescimento Humano/sangue , Humanos , Hipoglicemia/induzido quimicamente , Insulina/efeitos adversos , Masculino
3.
Scand J Immunol ; 87(1): 46-53, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29125655

RESUMO

B cells have recently entered the stage as an important accessory player in type 1 diabetes (T1D) etiopathogenesis. Experimental studies suggest regulatory functions of vitamin D on B cells. However, only a few human studies, with considerable methodological limitations, have been conducted within this field. Our objective was to investigate whether higher 25-hydroxyvitamin D (25(OH)D) concentrations were inversely associated with ß-cell autoantigens glutamic acid decarboxylase (isoform 65) (GADA) and insulinoma-associated antigen-2A (IA-2A). Further, we also wanted to examine the relationship between 25(OH)D and total antibody concentrations. We randomly selected 500 patients with newly diagnosed T1D and 500 siblings for 25(OH)D, antibody and genetic analysis from the population-based Danish Registry of Childhood and Adolescent Diabetes. The relative change (RC) in the mean concentration of GADA, IA-2A and antibody isotypes by a 10 nmol/l increase in 25(OH)D concentration was modelled by a robust log-normal regression model. We found no association between 25(OH)D and GADA [adjusted RC per 10 nmol/l increase: 1.00; 95% confidence interval (CI): 0.98-1.02] and IA-2A [adjusted RC per 10 nmol/l increase: 0.92; CI: 0.76-1.12]. Further, 25(OH)D was not associated with the total concentration of antibody isotypes [immunoglobulin (Ig)A, IgE, IgG and IgM]. All null findings were unaltered after adjustment for genetic variation in the vitamin D pathway. Physiological concentrations of 25(OH)D are unlikely to have a clinically important effect on antibody concentrations in a paediatric population of newly diagnosed patients with T1D and their healthy siblings.


Assuntos
Autoantígenos/sangue , Diabetes Mellitus Tipo 1/imunologia , Isotipos de Imunoglobulinas/sangue , Vitamina D/análogos & derivados , Estudos de Casos e Controles , Criança , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/genética , Feminino , Glutamato Descarboxilase/sangue , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Proteínas Tirosina Fosfatases Classe 8 Semelhantes a Receptores/sangue , Irmãos , Vitamina D/sangue
4.
Diabet Med ; 34(3): 380-386, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27027777

RESUMO

AIM: To determine the mortality rate in a Danish cohort of children and adolescents diagnosed with Type 1 diabetes mellitus compared with the general population. METHODS: In 1987 and 1989 we included 884 children and 1020 adolescents aged 20 years and under, corresponding to 75% of all Danish children and adolescents with Type 1 diabetes, in two nationwide studies in Denmark. Those who had participated in both investigations (n = 720) were followed until 1 January 2014, using the Danish Civil Registration System on death certificates and emigration. We derived the expected number of deaths in the cohort, using population data values from Statistics Denmark to calculate the standardized mortality ratio. Survival analysis was performed using Cox proportional hazards model. RESULTS: During the 24 years of follow-up, 49 (6.8%) patients died, resulting in a standardized mortality ratio of 4.8 (95% confidence interval 3.5, 6.2) compared with the age-standardized general population. A 1% increase in baseline HbA1c (1989), available in 718 of 720 patients, was associated with all-cause mortality (hazard ratio = 1.38; 95% confidence interval 1.2, 1.6; P < 0.0001). Type 1 diabetes with multiple complications was the most common reported cause of death (36.7%). CONCLUSION: We found an increased mortality rate in this cohort of children and adolescents with Type 1 diabetes compared with the general population. The only predictor for increased risk of death up to 24 years after inclusion was the HbA1c level in 1989. This emphasizes the importance of achieving optimal metabolic control in young people with Type 1 diabetes.


Assuntos
Complicações do Diabetes/fisiopatologia , Diabetes Mellitus Tipo 1/complicações , Adolescente , Adulto , Biomarcadores/sangue , Criança , Estudos de Coortes , Estudos Transversais , Dinamarca/epidemiologia , Complicações do Diabetes/mortalidade , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/mortalidade , Diabetes Mellitus Tipo 1/fisiopatologia , Progressão da Doença , Feminino , Seguimentos , Hemoglobina A Glicada/análise , Humanos , Masculino , Mortalidade , Estudos Prospectivos , Sistema de Registros , Análise de Sobrevida , Adulto Jovem
5.
Diabetes Res Clin Pract ; 109(2): 279-86, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26070217

RESUMO

AIM: This prospective study aimed to identify and estimate the frequency of responders offered Continuous subcutaneous insulin infusion (CSII) from baseline data and during follow-up, and secondly to characterize CSII users with good adherence to pump therapy among 463 children and adolescents with Type 1 diabetes mellitus. METHODS: A response was defined as lowering HbA1c with 1% or achieving an HbA1c<7.5% (58 mmol/mol). Good adherence was defined as measuring ≥7 self monitored blood glucoses (SMBGs) and taking ≥7 boluses daily. Logistic regression was used to estimate the effect of demographic and clinical variables prior to and during pump treatment. RESULTS: At 24 months follow-up 32% qualified as responders. Stratifying for age at onset, 45% of the children aged <6 yrs qualified as responders vs. 32% and 28% of the youngsters and adolescents aged 6-12 yrs. and 12-19 yrs., respectively (p=0.02). Responders were characterized by their HbA1c-level at pump onset (p=0.001), taking more daily boluses (7.64 ± 3.33 vs. 6.40 ± 3.18 p=0.003) and measuring more SMBGs per day at follow-up (6.88 ± 2.35 vs. 6.31 ± 2.54 p=0.03). The incidence of severe hypoglycemia decreased from 14.3 to 3.3 events per 100 person years (p<0.0001). Twenty percent did not respond despite a good adherence toward CSII therapy. CONCLUSION: Age <6 years, high or low HbA1c at pump initiation and number of daily boluses were associated with improved or sustained near-normal metabolic outcome. The incidence of severe hypoglycemia was significantly reduced. Twenty percent of the population had good adherence without any metabolic improvement.


Assuntos
Diabetes Mellitus Tipo 1/sangue , Hemoglobina A Glicada/metabolismo , Insulina/administração & dosagem , Adolescente , Automonitorização da Glicemia , Criança , Dinamarca/epidemiologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/epidemiologia , Feminino , Humanos , Hipoglicemiantes/administração & dosagem , Incidência , Injeções Subcutâneas , Sistemas de Infusão de Insulina , Masculino , Estudos Prospectivos
6.
Pediatr Diabetes ; 16(4): 256-62, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25082292

RESUMO

AIMS: Few studies have looked at nationwide data for insulin pump treatment. Since 1996 the Danish Childhood Diabetes Registry (DanDiabKids) has collected data on all Danish diabetic patients aged 0-15 yr. The purpose of this study is to evaluate the prevalence of continuous subcutaneous insulin infusion (CSII) use among Danish children with diabetes and to compare metabolic control in CSII-treated children and adolescents to those treated with MDI. MATERIALS AND METHODS: The Registry collects on a yearly basis data on insulin regimen, central measured hemoglobin A1c (HbA1c), and demographic data on all patients. In the period 2005-2011, 2983 young patients (1721 males) with diabetes were followed in the Registry. Mean observation period was 5.11 yr [standard error (SE) 0.09]. In the total period 1846 patients were treated with MDI and 1493 changed from MDI to CSII. In 2005, less than 5% of children were treated with CSII whereas the percentage of children on CSII increased to approximately 50% in 2011. The patients were divided into age groups, <5 yr, 5-10 yr, and > 15 yr. RESULTS: HbA1c was significantly higher in MDI-treated children, +5.29 (CI 95% 4.29; 6.29 mmol/mol). HbA1c in all age groups was significantly lower in CSII-treated patients, and longitudinally HbA1c continued to be lower in all age groups. In multivariate analysis, a low HbA1c at CSII start, centers with more than 100 pump patients, a more recent year of diabetes onset, a higher number of self-monitoring of blood glucose (SMBG) measurements, a higher number of daily boluses, and a higher percentage of bolus insulin were all related to a lower HbA1c. CONCLUSION: The percentage of children on pumps (CSII) is CSII treatment is associated with a significantly lower Hba1c, achieved just after treatment initiation. In the following years there is a parallel rise in HbA1c in both MDI as well as in MDI treated patients. Patients coming from larger clinics, and patients measuring more blood glucose values and taking more boluses have a better metabolic control.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Sistemas de Infusão de Insulina/estatística & dados numéricos , Insulina/administração & dosagem , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Dinamarca , Diabetes Mellitus Tipo 1/metabolismo , Feminino , Humanos , Masculino , Resultado do Tratamento
7.
Acta Diabetol ; 52(3): 591-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25528006

RESUMO

AIMS: To examine contemporary rates of severe hypoglycemia (SH) and identify the effect of predictors of SH in a pediatric type 1 diabetes population. METHODS: The national diabetes register provided data on children residing in Denmark from 2008 to 2013 in this register-based population study. Robust Poisson regression models were applied. RESULTS: The study population [n = 2,715 (50.9 % boys), mean (SD) age at onset; 8.1 (4.0) years, diabetes duration; 5.6 (4.9) years] comprised 7,390 person-years of data and 561 events of SH. The overall incidence of SH was 7.6 per 100 person-years. The incidence rate peaked with 16.0 per 100 person-years in 2008 reaching a nadir of 4.9 in 2011. Overall, insulin pump reduced the rate of SH with 27 % compared to any pen treatment (P = 0.003). When stratifying pen treatment, premixed insulin increased the rate of SH by 1.9-fold (P = 0.0015) and NPH increased the rate by 1.6-fold (P = 0.003) versus pump treatment, whereas long-acting insulin analogues were comparable with pump treatment (P = 0.1485). We found no association of SH with glycemic control (P > 0.05). CONCLUSIONS: A nationwide halving in rates of severe hypoglycemia was observed during the study period independent of the prevailing average HbA1c level. Changes in diabetes care and successful educational programs may have influenced the lower incidence rate of severe hypoglycemia.


Assuntos
Diabetes Mellitus Tipo 1/epidemiologia , Hipoglicemia/epidemiologia , Adolescente , Criança , Pré-Escolar , Dinamarca/epidemiologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Feminino , Humanos , Hipoglicemia/tratamento farmacológico , Insulina/administração & dosagem , Masculino
8.
Scand J Immunol ; 80(6): 452-61, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25201044

RESUMO

The mechanisms by which antigen-specific T cells migrate to the islets of Langerhans in type 1 diabetes (T1D) are largely unknown. Chemokines attract immune cells to sites of inflammation. The aim was to elucidate the role of inflammatory chemokines in T1D at time of diagnosis. From a population-based registry of children diagnosed with T1D from 1997 to 2005, we studied five different inflammatory chemokines (CCL2, CCL3, CCL4, CCL5 and CXCL8). Four hundred and eighty-two cases and 479 sibling frequencies matched on age and sample year distribution were included. Patients showed lower levels of CCL4 compared to siblings, but this result was not significant after correction for multiple testing. CCL2, CCL3, CCL4 and CXCL8 levels were highest in the most recent cohorts (P < 0.01) in both patients and siblings. A significant seasonal variation - for most of the chemokines - was demonstrated with the highest level during the summer period in both patients and siblings. In addition, there was a significant inverse relationship between CCL4 levels and age. When comparing patients and siblings, remarkably few differences were identified, but interestingly chemokine levels varied with age, season and period for the entire study population. Such variations should be taken into account when studying chemokines in paediatric populations.


Assuntos
Quimiocina CCL2/sangue , Quimiocina CCL3/sangue , Quimiocina CCL4/sangue , Diabetes Mellitus Tipo 1/sangue , Interleucina-8/sangue , Irmãos , Adolescente , Fatores Etários , Autoanticorpos/sangue , Autoanticorpos/imunologia , Biomarcadores/sangue , Estudos de Casos e Controles , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/imunologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Sistema de Registros , Estações do Ano , Fatores Sexuais , Fatores de Tempo
9.
Diabetologia ; 56(5): 995-1003, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23389397

RESUMO

AIMS/HYPOTHESIS: We investigated the long-term impact of diabetic ketoacidosis (DKA) at onset on metabolic regulation and residual beta cell function in a Danish population with type 1 diabetes. METHODS: The study is based on data from DanDiabKids, a Danish national diabetes register for children. The register provides clinical and biochemical data on patients with type 1 diabetes diagnosed in 1996-2009 and then followed-up until 1 January 2012. Repeated-measurement models were used as statistical methods. RESULTS: The study population comprised 2,964 children <18 years. The prevalence of DKA at diagnosis was 17.9%. Of the total subjects, 8.3% had mild, 7.9% had moderate and 1.7% had severe DKA. DKA (moderate and severe) was associated with increased HbA1c (%) levels (0.24; 95% CI 0.11, 0.36; p = 0.0003) and increased insulin dose-adjusted HbA1c (IDAA1c, 0.51; 95% CI 0.31, 0.70; p < 0.0001) during follow-up, after adjustment for covariates. Children without a family history of diabetes were more likely to present with DKA (19.2% vs 8.8%, p < 0.0001); however, these children had a lower HbA1c (%) level over time (-0.35; 95% CI -0.46, -0.24; p < 0.0001). Continuous subcutaneous insulin infusion (CSII) was associated with a long-term reduction in HbA1c, changing the effect of DKA, after adjustment for covariates (p < 0.0001). CONCLUSIONS/INTERPRETATION: DKA at diagnosis was associated with poor long-term metabolic regulation and residual beta cell function as assessed by HbA1c and IDAA1c, respectively; however, CSII treatment was associated with improvement in glycaemic regulation and residual beta cell function, changing the effect of DKA at onset in our population.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Cetoacidose Diabética/etiologia , Hiperglicemia/etiologia , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Adolescente , Biomarcadores/sangue , Criança , Pré-Escolar , Dinamarca/epidemiologia , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/fisiopatologia , Cetoacidose Diabética/epidemiologia , Cetoacidose Diabética/prevenção & controle , Monitoramento de Medicamentos , Feminino , Hemoglobina A Glicada/análise , Humanos , Hiperglicemia/epidemiologia , Hiperglicemia/prevenção & controle , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/uso terapêutico , Insulina/administração & dosagem , Insulina/sangue , Insulina/uso terapêutico , Sistemas de Infusão de Insulina , Secreção de Insulina , Estudos Longitudinais , Masculino , Prevalência , Prognóstico , Sistema de Registros , Índice de Gravidade de Doença
10.
Mol Ecol ; 20(8): 1624-34, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21366749

RESUMO

Sex-biased dispersal is observed in many taxa, but few studies have compared sex-biased dispersal among and within populations. We addressed the magnitude and habitat dependency of sex-biased dispersal in social African striped mice by separating group-related from population-related genetic variance to understand the contribution of each sex to deme structure. As dispersal over unoccupied habitat is likely to be more costly than dispersal within a population, we predicted that individuals leaving the natal population have a lower body condition, being inferior to heavier territorial individuals. Fine-scale genetic structure was detected in both sexes. Female relatedness decreased continuously from R = 0.21 at 25 m to zero at 500 m. Maximum male relatedness R = 0.05 was constant at distances between 25 and 75 m, becoming zero at 100 m. Genetic variance (F(ST) ) among seven locations was significantly higher in females than in males, while inbreeding estimates (F(IS) ) were significantly higher in males than in females. Assignment tests estimated significantly more migrants among males, while Bayesian clustering estimated only a single genetic unit cluster for males among the seven locations. The mean body mass of migrant males (44 g) was significantly lower than for males that remained resident and thus dispersed within their sub-population (48 g). Combined, the results showed habitat-independent male-biased dispersal and high female philopatry, and suggested that body condition was more important than kinship in male dispersal decisions. We suggest that locally inferior males are important for gene flow between sub-populations. Thus, males might follow alternative dispersal tactics.


Assuntos
Fluxo Gênico , Variação Genética , Genética Populacional , Murinae/genética , Comportamento Sexual Animal , Animais , Teorema de Bayes , Tamanho Corporal , Ecossistema , Feminino , Heterozigoto , Endogamia , Masculino , Camundongos , Análise de Sequência de DNA , África do Sul
11.
J Evol Biol ; 22(5): 1137-42, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-21462423

RESUMO

Colonial social spiders experience extreme inbreeding and highly restricted gene flow between colonies; processes that question the genetic cohesion of geographically separated populations and which could imply multiple origins from predecessors with limited gene flow. We analysed species cohesion and the potential for long-distance dispersal in the social spider Stegodyphus dumicola by studying colony structure in eastern South Africa and the cohesion between this population and Namibian populations previously published. Data from both areas were (re)analysed for historic demographic parameters. Eastern South African S. dumicola were closely related to an east Namibian lineage, showing cohesion of S. dumicola relative to its sister species. Colony structure was similar in both areas with mostly monomorphic colonies, but haplotype diversity was much reduced in eastern South Africa. Here, the population structure indicated recent population expansion. By contrast, Namibia constitutes an old population, possibly the geographic origin of the species. Both the comparison of the eastern South African and Namibian lineages and the distribution within eastern South Africa show the potential for long-distance dispersal in few generations via colony propagation.


Assuntos
Variação Genética , Genética Populacional , Endogamia , Comportamento Social , Aranhas/genética , Animais , Sequência de Bases , Análise por Conglomerados , DNA Mitocondrial/genética , Demografia , Haplótipos/genética , Funções Verossimilhança , Modelos Genéticos , Dados de Sequência Molecular , Namíbia , Dinâmica Populacional , Análise de Sequência de DNA , África do Sul , Especificidade da Espécie
12.
J Evol Biol ; 19(3): 705-16, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16674567

RESUMO

The fate of species integrity upon natural hybridization depends on the interaction between selection and dispersal. The relative significance of these processes may be studied in the initial phase of contact before selection and gene flow reach equilibrium. Here we study a hybrid zone of two salamander species, Lyciasalamandra antalyana and Lyciasalamandra billae, at the initial phase of hybridization. We quantify the degree and mode of introgression using nuclear and mtDNA markers. The hybrid zone can be characterized as an abrupt transition zone, the central hybrid zone being only c. 400 m, but introgressed genes were traced up to 3 km. Introgression was traced in both sexes but gene flow may be slightly male-biased. Indirect evidence suggests that hybrid males are less viable than females. Introgression occurred at two levels: (1) locus-specific selection led to different allelic introgression patterns independent of species, while (2) asymmetrical species-level introgression occurred predominately from L. antalyana to L. billae due to range expansion of the former. This indicates that foreign genes can be incorporated into novel genomic environments, which in turn may contribute to the great diversity of morphological variants in Lyciasalamandra.


Assuntos
Anfíbios , Anfíbios/genética , Animais , Simulação por Computador , Enzimas/genética , Evolução Molecular , Feminino , Fluxo Gênico , Hibridização Genética , Masculino , Polimorfismo Genético , Seleção Genética , Comportamento Sexual Animal
13.
Heredity (Edinb) ; 96(5): 410-8, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16570066

RESUMO

We address the controversy over the processes causing divergence during speciation. Host races of the fruit fly Tephritis conura attack the thistles Cirsium oleraceum and Cirsium heterophyllum. By studying the genetic divergence of T. conura in areas where host plants are sympatric, parapatric and allopatric, we assessed the contribution of geography in driving host-race divergence. We also evaluated the relative importance of genetic drift and selection in the diversification process, by analysis of the geographic distribution of genetic variation. Host races were significantly diverged at five out of 13 polymorphic allozyme loci. Variance at two loci, Hex and Pep D, was almost exclusively attributable to host-plant affiliation in all geographic settings. However, Hex was significantly more differentiated between host races in sympatry/parapatry than in allopatry. This result might be explained by selection against hybridisation or against incorrect host choice in contact areas. Linkage disequilibrium tests suggest the latter: gene flow in contact areas may occur from males of the host-race C. heterophyllum to females of the host-race C. oleraceum, whereas incorrect oviposition events were never observed. The distinctive patterns of genetic differentiation at the two highly differentiated loci implicate the action of selection (acting directly or on linked loci) rather than genetic drift. Despite their restricted interactions in sympatry, we conclude that host races are stable and that the major diversification process took place before species arrived in today's geographical settings.


Assuntos
Especiação Genética , Tephritidae/genética , Animais , Frequência do Gene , Geografia , Polimorfismo Genético
14.
Eur Psychiatry ; 20(7): 474-83, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15967642

RESUMO

Quality of life (QoL) measures are increasingly recognized as necessary parts of outcome assessments in psychosis. The present paper is a comprehensive study of patients with first-episode psychosis where QoL is measured by the commonly used Lehman Quality of Life Interview (L-QoLI). The aim is to examine if the L-QoLI maintain its original structure when used in a group of patients with first-episode psychosis, and to investigate what determines global subjective QoL with a specific emphasis on premorbid adjustment, duration of untreated psychosis (DUP) and clinical symptoms. The study indicates that the psychometric properties of the L-QoLI do not change significantly when used in first-episode samples. The patients report subjective and objective QoL in the fair to good range, with only a moderate association between the objective and subjective measures. Poor global satisfaction is predicted by being single, abusing drugs, being depressed, having a diagnosis of psychotic affective disorder, having poor premorbid social adjustment and DUP over 10 weeks. The study supports the notion that patients with first-episode psychosis construct QoL in the same way as other groups, and that longer durations of compromised function at this stage produces poor satisfaction with life rather than a downward readjustment of expectations.


Assuntos
Transtornos Psicóticos/diagnóstico , Qualidade de Vida/psicologia , Inquéritos e Questionários , Atividades Cotidianas , Adolescente , Adulto , Demografia , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Psicóticos/etiologia , Transtornos Psicóticos/terapia , Esquizofrenia/complicações , Índice de Gravidade de Doença
15.
Acta Psychiatr Scand ; 112(1): 64-71, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15952947

RESUMO

OBJECTIVE: Impairments in laboratory tasks of metacognition appear to be associated with symptoms, functioning, and neurocognition in schizophrenia. We sought to replicate these results in a study of metacognition within personal narratives of self and illness. METHOD: Narratives of 61 men with schizophrenia were rated using the Metacognition Assessment Scale and correlated with concurrent assessment of symptoms, quality of life, neurocognition and insight. RESULTS: Controlling for age and education, understanding of one's own mind was linked with better neurocognition across multiple domains, and lesser emotional withdrawal. Greater understanding of other's mind was linked with better verbal memory and less emotional withdrawal. Greater metacognition in the context of purposeful problem solving was associated with better verbal memory, insight and social function, and less emotional withdrawal and paranoia. CONCLUSION: Deficits in metacognition within the narratives of persons with schizophrenia are linked with symptoms, quality of life, neurocognition and poorer awareness of illness.


Assuntos
Atitude Frente a Saúde , Transtornos Cognitivos/epidemiologia , Narração , Qualidade de Vida/psicologia , Esquizofrenia/epidemiologia , Autoimagem , Adulto , Transtornos Cognitivos/diagnóstico , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Resolução de Problemas , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico , Índice de Gravidade de Doença
16.
Heredity (Edinb) ; 93(4): 342-9, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15241447

RESUMO

Bat-swarming sites where thousands of individuals meet in late summer were recently proposed as 'hot spots' for gene flow among populations. If, due to female philopatry, nursery colonies are genetically differentiated, and if males and females of different colonies meet at swarming sites, then we would expect lower differentiation of maternally inherited genetic markers among swarming sites and higher genetic diversity within. To test these predictions, we compared genetic variance from three swarming sites to 14 nursery colonies. We analysed biparentally (five nuclear and one sex-linked microsatellite loci) and maternally (mitochondrial D-loop, 550 bp) inherited molecular markers. Three mtDNA D-loop haplolineages that were strictly separated at nursery colonies were mixed at swarming sites. As predicted by the 'extra colony-mating hypothesis', genetic variance among swarming sites (V(ST)) for the D-loop drastically decreased compared to the nursery population genetic variance (V(PT)) (31 and 60%, respectively), and genetic diversity increased at swarming sites. Relatedness was significant at nursery colonies but not at swarming sites, and colony relatedness of juveniles to females was positive but not so to males. This suggests a breakdown of colony borders at swarming sites. Although there is behavioural and physiological evidence for sexual interaction at swarming sites, this does not explain why mating continues throughout the winter. We therefore propose that autumn roaming bats meet at swarming sites across colonies to start mating and, in addition, to renew information about suitable hibernacula.


Assuntos
Quirópteros/genética , Pool Gênico , Variação Genética , Animais , DNA Mitocondrial , Feminino , Marcadores Genéticos/genética , Genética Populacional , Masculino , Repetições de Microssatélites/genética , Análise de Sequência de DNA
17.
Scand J Immunol ; 59(6): 582-91, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15182254

RESUMO

CD4 is a candidate gene in autoimmune diseases, including Type 1 diabetes mellitus (T1DM), because the CD4 receptor is crucial for appropriate antigen responses of CD4(+) T cells. We previously found linkage between a CD4-1188(TTTTC)(5-14) promoter polymorphism and T1DM. In the present study, we screened the human CD4 promoter for mutations and identified three frequent single nucleotide polymorphisms (SNPs): CD4-181C/G, CD4-521C/G and CD4-1050T/C. The SNPs are in strong linkage disequilibrium (LD) and association with the CD4-1188(TTTTC)(5-14) alleles, and we observed nine CD4 promoter haplotypes, of which four are frequent. We genotyped the SNPs in 253 Danish T1DM families (1129 individuals) and found evidence for linkage and association of a CD4 (A4(-1188)T(-1050)G(-521)C(-181)) haplotype to T1DM. In reporter studies, we show that (1) the T1DM-associated CD4 haplotype encodes high constitutive promoter activity and (2) the CD4-181G variant encodes higher stimulated promoter activity than the CD4-181C variant. This difference is in part neutralized in the frequently occurring CD4 promoter haplotypes by the more upstream genetic variants. Thus, we report functional impact of a novel CD4-181C/G SNP on stimulated CD4 promoter activity and the identification of a novel CD4 haplotype with high constitutive promoter activity that is linked and associated with T1DM.


Assuntos
Antígenos CD4/genética , Diabetes Mellitus Tipo 1/genética , Predisposição Genética para Doença , Regiões Promotoras Genéticas , Adolescente , Antígenos CD4/imunologia , Criança , Dinamarca , Diabetes Mellitus Tipo 1/imunologia , Feminino , Frequência do Gene , Haplótipos , Humanos , Desequilíbrio de Ligação/genética , Masculino , Mutação , Reação em Cadeia da Polimerase , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único/genética , Sequências de Repetição em Tandem/genética
19.
Diabet Med ; 21(3): 218-22, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15008830

RESUMO

AIMS: To investigate whether the WFS1 gene, the gene for Wolfram syndrome, is a susceptibility gene for more common forms of diabetes in the Danish population. METHODS: One hundred and fifty-two Danish Type 1 diabetes mellitus sib-pair families were genotyped for two microsatellite markers situated within 5 cM of the WFS1 gene and analysed for linkage and association using the sib-TDT. The entire coding region, the 5'UTR and 3'UTR of the WFS1 gene, were screened for mutations by direct sequencing in 29 selected Type 1 diabetes patients. Four of the identified mutations were tested for linkage and association in 255 Danish Type 1 diabetes families (including 103 simplex families). RESULTS: Evidence for linkage to Type 1 diabetes was found as the second most frequent allele of the marker D4S394 were transmitted 137 times (T = 61%) and not transmitted 88 times to affected offspring (Puc = 0.0011). Twelve mutations were found in the coding region and three mutations in the 3'UTR. No evidence for linkage and association to Type 1 diabetes was found testing four of the identified amino acid substitutions. CONCLUSIONS: Evidence of linkage to Type 1 diabetes was observed in the Danish family collection. However, no evidence of linkage and association was observed for any of the analysed polymorphisms, suggesting that other variations must be responsible for the observed evidence of linkage in the region.


Assuntos
Cromossomos Humanos Par 4/genética , Diabetes Mellitus Tipo 1/genética , Ligação Genética/genética , Proteínas de Membrana/genética , Idade de Início , Alelos , Dinamarca , Saúde da Família , Marcadores Genéticos/genética , Predisposição Genética para Doença/genética , Testes Genéticos/métodos , Genótipo , Humanos , Repetições de Microssatélites/genética , Mutação/genética , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Nucleotídeo Único/genética
20.
J Evol Biol ; 17(1): 83-93, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15000651

RESUMO

The fruit fly Tephritis bardanae infests flower heads of two burdock hosts, Arctium tomentosum and A. minus. Observations suggest host-associated mating and behavioural differences at oviposition indicating host-race status. Previously, flies from each host plant were found to differ slightly in allozyme allele frequencies, but these differences could as well be explained by geographical separation of host plants. In the present study, we explicitly test whether genetic and morphological variance among T. bardanae are explained best by host-plant association or by geographical location, and if this pattern is stable over a 10-year period. Populations of A. tomentosum flies differed significantly from those of A. minus flies in (i) allozyme allele frequencies at the loci Pep-A and Pgd, (ii) mtDNA haplotype frequencies and (iii) wing size. In contrast, geographical location had no significant influence on the variance estimates. While it remains uncertain whether morphometric differentiation reflects genotypic variability or phenotypic plasticity, allozyme and mtDNA differentiation is genetically determined. This provides strong evidence for host-race formation in T. bardanae. However, the levels of differentiation are relatively low indicating that the system is in an early stage of divergence. This might be due to a lack of time (i.e. the host shift occurred recently) or due to relatively high gene flow preventing much differentiation at loci not experiencing selection.


Assuntos
Meio Ambiente , Variação Genética , Tephritidae/genética , Análise de Variância , Animais , Arctium/fisiologia , Sequência de Bases , Pesos e Medidas Corporais , Análise por Conglomerados , Primers do DNA , DNA Mitocondrial/genética , Inglaterra , Frequência do Gene , Geografia , Haplótipos/genética , Isoenzimas , Dados de Sequência Molecular , Análise de Sequência de DNA , Tephritidae/anatomia & histologia , Asas de Animais/anatomia & histologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA