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1.
Artigo em Inglês | MEDLINE | ID: mdl-39225898

RESUMO

Family accommodation (FA) is widely-recognised as an important clinical phenomenon in obsessive-compulsive disorder (OCD) and anxiety disorders, and is related to poorer treatment outcomes. However, FA has not been quantitatively explored in Body Dysmorphic Disorder (BDD). The aim of this study was to investigate the patterns and correlates of maternal accommodation in adolescent BDD, and its association with treatment outcomes. Participants were 131 adolescents with BDD and their mothers who completed the Family Accommodation Scale-Parent Report (FAS-PR) as part of routine clinical practice in a National and Specialist Service for Young People at the Maudsley Hospital, London. Seventy-six (58%) young people received specialist cognitive behavioural therapy for BDD and had post-treatment data available. All mothers engaged in at least one form of accommodation. Providing reassurance (98.5%) and assisting avoidance (88.5%) were the most commonly endorsed behaviours. Levels of accommodation were positively associated with clinician-rated BDD symptom severity (r = 0.18, p = 0.041) and maternal symptoms of anxiety, depression and stress (r = 0.41, p < 0.001), and negatively associated with child global functioning (r = -0.38, p < 0.001). Maternal accommodation did not predict treatment outcomes (ß = 0.055, p > 0.05). The findings indicate that maternal accommodation is common and has important clinical correlates, but does not impact on treatment response. Consequently, the relationship between maternal accommodation and BDD symptoms may differ to that evidenced in paediatric OCD. Future longitudinal research exploring maternal and paternal accommodation, and assessing variables of interest at multiple time-points throughout treatment, is needed to advance understanding of the role of FA in adolescent BDD.

2.
Psychol Med ; 53(3): 1106-1114, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-34474701

RESUMO

BACKGROUND: Anxiety disorders are highly prevalent with an early age of onset. Understanding the aetiology of disorder emergence and recovery is important for establishing preventative measures and optimising treatment. Experimental approaches can serve as a useful model for disorder and recovery relevant processes. One such model is fear conditioning. We conducted a remote fear conditioning paradigm in monozygotic and dizygotic twins to determine the degree and extent of overlap between genetic and environmental influences on fear acquisition and extinction. METHODS: In total, 1937 twins aged 22-25 years, including 538 complete pairs from the Twins Early Development Study took part in a fear conditioning experiment delivered remotely via the Fear Learning and Anxiety Response (FLARe) smartphone app. In the fear acquisition phase, participants were exposed to two neutral shape stimuli, one of which was repeatedly paired with a loud aversive noise, while the other was never paired with anything aversive. In the extinction phase, the shapes were repeatedly presented again, this time without the aversive noise. Outcomes were participant ratings of how much they expected the aversive noise to occur when they saw either shape, throughout each phase. RESULTS: Twin analyses indicated a significant contribution of genetic effects to the initial acquisition and consolidation of fear, and the extinction of fear (15, 30 and 15%, respectively) with the remainder of variance due to the non-shared environment. Multivariate analyses revealed that the development of fear and fear extinction show moderate genetic overlap (genetic correlations 0.4-0.5). CONCLUSIONS: Fear acquisition and extinction are heritable, and share some, but not all of the same genetic influences.


Assuntos
Extinção Psicológica , Medo , Humanos , Medo/fisiologia , Extinção Psicológica/fisiologia , Condicionamento Clássico/fisiologia , Ansiedade , Gêmeos Dizigóticos/genética
3.
Psychol Med ; 53(12): 5428-5441, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-35879886

RESUMO

BACKGROUND: The impact of the coronavirus disease 2019 (COVID-19) pandemic on mental health is still being unravelled. It is important to identify which individuals are at greatest risk of worsening symptoms. This study aimed to examine changes in depression, anxiety and post-traumatic stress disorder (PTSD) symptoms using prospective and retrospective symptom change assessments, and to find and examine the effect of key risk factors. METHOD: Online questionnaires were administered to 34 465 individuals (aged 16 years or above) in April/May 2020 in the UK, recruited from existing cohorts or via social media. Around one-third (n = 12 718) of included participants had prior diagnoses of depression or anxiety and had completed pre-pandemic mental health assessments (between September 2018 and February 2020), allowing prospective investigation of symptom change. RESULTS: Prospective symptom analyses showed small decreases in depression (PHQ-9: -0.43 points) and anxiety [generalised anxiety disorder scale - 7 items (GAD)-7: -0.33 points] and increases in PTSD (PCL-6: 0.22 points). Conversely, retrospective symptom analyses demonstrated significant large increases (PHQ-9: 2.40; GAD-7 = 1.97), with 55% reported worsening mental health since the beginning of the pandemic on a global change rating. Across both prospective and retrospective measures of symptom change, worsening depression, anxiety and PTSD symptoms were associated with prior mental health diagnoses, female gender, young age and unemployed/student status. CONCLUSIONS: We highlight the effect of prior mental health diagnoses on worsening mental health during the pandemic and confirm previously reported sociodemographic risk factors. Discrepancies between prospective and retrospective measures of changes in mental health may be related to recall bias-related underestimation of prior symptom severity.


Assuntos
COVID-19 , Transtornos de Estresse Pós-Traumáticos , Feminino , Humanos , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , COVID-19/epidemiologia , Pandemias , Depressão/psicologia , Estudos Retrospectivos , Estudos Prospectivos , SARS-CoV-2 , Ansiedade/psicologia , Reino Unido/epidemiologia
4.
Eur Child Adolesc Psychiatry ; 32(7): 1201-1210, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34914003

RESUMO

Despite the high comorbidity, surprisingly little is known about the clinical features, treatment prognosis, and treatment mediators for youth with Obsessive-Compulsive Disorder (OCD) and Autism Spectrum Disorder (ASD). This study, the largest to date, compared 172 young people with OCD and ASD (OCD + ASD) to 447 without ASD (OCD) on clinical characteristics, finding those with OCD + ASD were more likely to endorse poorer insight into their OCD, have greater global functional impairment, greater levels of concurrent psychopathology, higher levels of family accommodation and to be on medication. Treatment outcomes following a course of Cognitive Behaviour Therapy with or without medication were explored for a subgroup; 100 young people with OCD + ASD and 223 with OCD. Whilst both groups benefitted from treatment, the OCD + ASD group had significantly poorer treatment outcomes. Greater global functional impairment and being on medication mediated the between-group difference in outcomes. Further research and treatment refinements are needed to improve outcomes for youth with OCD + ASD.


Assuntos
Transtorno do Espectro Autista , Transtorno Obsessivo-Compulsivo , Adolescente , Humanos , Transtorno do Espectro Autista/complicações , Transtorno do Espectro Autista/terapia , Transtorno do Espectro Autista/epidemiologia , Resultado do Tratamento , Transtorno Obsessivo-Compulsivo/complicações , Transtorno Obsessivo-Compulsivo/terapia , Transtorno Obsessivo-Compulsivo/epidemiologia , Prognóstico , Comorbidade
5.
J Child Psychol Psychiatry ; 61(9): 979-987, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31950513

RESUMO

BACKGROUND: Anxiety sensitivity, the tendency to fear the symptoms of anxiety, is a key risk factor for the development anxiety disorders. Although obsessive-compulsive disorder was previously classified as an anxiety disorder, the prospective relationship between anxiety sensitivity and obsessive-compulsive symptoms (OCS) has been largely overlooked. Furthermore, a lack of genetically informative studies means the aetiology of the link between anxiety sensitivity and OCS remains unclear. METHODS: Adolescent twins and siblings (N = 1,579) from the G1219 study completed self-report questionnaires two years apart assessing anxiety sensitivity, OCS, anxiety and depression. Linear regression models tested prospective associations between anxiety sensitivity and OCS, with and without adjustment for anxiety and depressive symptoms. A phenotypic cross-lagged model assessed bidirectional influences between anxiety sensitivity and OCS over time, and a genetic version of this model examined the aetiology of these associations. RESULTS: Anxiety sensitivity was prospectively associated with changes in OCS, even after controlling for comorbid anxiety and depressive symptoms. The longitudinal relationship between anxiety sensitivity and OCS was bidirectional, and these associations were predominantly accounted for by nonshared environmental influences. CONCLUSIONS: Our findings are consistent with the notion that anxiety sensitivity is a risk factor for OCS during adolescence, but also suggest that experiencing OCS confers risk for heightened anxiety sensitivity. The reciprocal links between OCS and anxiety sensitivity over time are likely to be largely mediated by nonshared environmental experiences, as opposed to common genes. Our findings raise the possibility that interventions aimed at ameliorating anxiety sensitivity could reduce risk for OCS, and vice versa.


Assuntos
Ansiedade/genética , Suscetibilidade a Doenças , Meio Ambiente , Transtorno Obsessivo-Compulsivo/genética , Gêmeos/genética , Gêmeos/psicologia , Adolescente , Ansiedade/epidemiologia , Criança , Comorbidade , Humanos , Estudos Longitudinais , Transtorno Obsessivo-Compulsivo/epidemiologia , Irmãos/psicologia , Adulto Jovem
6.
Cogn Behav Ther ; 48(5): 353-368, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30221589

RESUMO

This study provides a preliminary exploration of factors which differentially predict treatment response to telephone-delivered cognitive behavioural therapy (TCBT) compared to face-to-face CBT (CBT) in a randomised non-inferiority controlled trial of 72 children (aged 11-18 years) with obsessive-compulsive disorder (OCD). Potential moderator variables, their interaction with treatment group (CBT, TCBT) and baseline levels of OCD severity were entered into separate regression models where the primary outcome measure was the post-intervention Children's Yale-Brown Obsessive-Compulsive Scale total score (CYBOCS). Separate regressions were also used to test associations between predictors and outcome controlling for pretreatment CYBOCS. Only pretreatment level of parent-rated child peer problems moderated the effects of the two interventions on CYBOCS severity at post-treatment. After controlling for baseline CYBOCS, only family accommodation rated by mothers predicted poorer outcomes in both groups. While CBT and TCBT may be equally effective for adolescents with OCD, the current results tentatively suggest that higher baseline level of peer problems strengthened the response to therapy for youth receiving TCBT and the predictor analyses reinforce the importance of directly addressing family accommodation during CBT for paediatric OCD regardless of delivery mode. Limitations of the current findings and directions for future work are discussed.


Assuntos
Terapia Cognitivo-Comportamental/métodos , Transtorno Obsessivo-Compulsivo/terapia , Adolescente , Criança , Feminino , Humanos , Masculino , Método Simples-Cego , Telefone , Resultado do Tratamento
7.
Psychol Med ; 45(7): 1539-49, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25498885

RESUMO

BACKGROUND: Little is known about the factors influencing the stability of obsessive-compulsive behaviour (OCB) from childhood to adolescence. The current study aimed to investigate: (1) the stability of paediatric OCB over a 12-year period; (2) the extent to which genetic and environmental factors influence stability; and (3) the extent to which these influences are stable or dynamic across development. METHOD: The sample included 14 743 twins from a population-based study. Parental ratings of severity of OCB were collected at ages 4, 7, 9 and 16 years. RESULTS: OCB was found to be moderately stable over time. The genetic influence on OCB at each age was moderate, with significant effects also of non-shared environment. Genetic factors exerted a substantial influence on OCB persistence, explaining 59-80% of the stability over time. The results indicated genetic continuity, whereby genetic influences at each age continue to affect the expression of OCB at subsequent ages. However, we also found evidence for genetic attenuation in that genetic influences at one age decline in their influence over time, and genetic innovation whereby new genes 'come on line' at each age. Non-shared environment influenced stability of OCB to a lesser extent and effects were largely unique to each age and displayed negligible influences on OCB at later time points. CONCLUSIONS: OCB appears to be moderately stable across development, and stability is largely driven by genetic factors. However, the genetic effects are not entirely constant, but rather the genetic influence on OCB appears to be a developmentally dynamic process.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Desenvolvimento Infantil/fisiologia , Doenças em Gêmeos/genética , Transtorno Obsessivo-Compulsivo/genética , Adolescente , Criança , Pré-Escolar , Doenças em Gêmeos/epidemiologia , Doenças em Gêmeos/etiologia , Inglaterra/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Transtorno Obsessivo-Compulsivo/epidemiologia , Transtorno Obsessivo-Compulsivo/etiologia , Índice de Gravidade de Doença , País de Gales/epidemiologia
8.
J Dairy Sci ; 98(10): 7248-63, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26254528

RESUMO

Proper performance monitoring of cows on pasture-based diets is crucial to inform nutritional recommendations that minimize undesirable effects of high ruminant CH4 emissions into the environment. The prediction of linkages between rumination patterns, methane emissions, and correlated production traits of cows in a pasture-based automatic milking system was tested. A previous 10-d baseline measurement of rumination activity by acoustic methodology of 156 Holstein-Friesian cows was used for frequency analysis of rumination time and identification of 2 treatment groups (n = 37 cows/group) represented by cows with consistently high (HR; 75th rumination percentile = 617.55 ± 81.37 min/d) or low (LR; 25th rumination percentile = 356.65 ± 72.67 min/d) rumination. The HR and LR cows were paired by nearest parity, days in milk, body weight (BW), and previous 10-d milk production, and within pairs randomly assigned to 1 of 2 experimental groups managed on a voluntary milking system with diets consisting of at least 75% pasture, plus concentrates. Animal traits, including rumination time, mass flux of CH4 (QCH4) and carbon dioxide (QCO2), milk production, and estimated dry matter intake according to individual QCO2 fluxes over a 22-d period were analyzed with repeated measure mixed models for a completely randomized design, structural equation modeling, and nonlinear regression. High rumination and methane was seen in older and heavier cows that had greater estimated dry matter intake and milk production. A consistent difference in rumination time and QCH4 across days was detected between HR and LR, even after adjustment for metabolic BW. Estimated dry matter intake had direct positive effects on rumination and QCH4, but no independent direct effect of rumination on QCH4 was detected. The LR cows produced more QCH4/milk, associated with lower milk, BW, concentrate intake, and greater activity at pasture. A typical dilution of maintenance effect on QCH4/milk was detected as a consequence of increasing milk yield and similar significant reduction of QCO2/milk. The results raise challenging questions regarding the rumination patterning of grazing dairy cows and alternatives to reduce ruminant methane emissions in grazing dairy cows.


Assuntos
Bovinos/fisiologia , Dieta/veterinária , Comportamento Alimentar , Metano/metabolismo , Leite/metabolismo , Animais , Automação , Peso Corporal , Indústria de Laticínios/instrumentação , Indústria de Laticínios/métodos , Feminino , Lactação , Dinâmica não Linear , Distribuição Aleatória
9.
Transl Anim Sci ; 6(4): txac141, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36381952

RESUMO

The feeding value for ruminants of green hemp biomass, from the low Δ9-tetrahydrocannabinol (Δ9-THC) variety of Cannabis sativa L., is unknown. Twelve Merino ewes were individually penned and randomly allocated on a stratified liveweight basis to one of two pelleted dietary treatments, control (0% hemp, n = 6) or hemp (42% green hemp biomass, n = 6) that delivered a diet meeting the nutrient requirements of the animals. The experimental period consisted of 17 d dietary and housing adaptation, followed by 7 d total urine and feces collection for determination of apparent nutrient digestibility. A ruminal fluid sample was collected on day 27 and assessed for pH, ammonia, volatile fatty acid (VFA), and cannabinoid concentrations. A blood sample from the jugular vein and incisional subcutaneous fat biopsy from an area around the base of the tail were collected on day 28 with additional fat biopsies taken 35 d and 140 d post-feeding to measure cannabinoids. The dry matter (DM), organic matter (OM), and crude protein (CP) digestibilities, along with total VFA concentration did not differ (P = 0.713) between the two diets; however, acid detergent fiber (ADF) and neutral detergent fiber (NDF) digestibilities (P < 0.001), water intake (P = 0.023), and fecal water output (P < 0.001) were significantly lower for the sheep-fed Hemp. Rumen pH did not vary (P = 0.256) between diets, but ruminal ammonia concentration was significantly lower (P = 0.024) for sheep consuming Hemp. Sheep-fed Hemp had significantly greater molar proportions of butyric (P = 0.039) and hexanoic (P = 0.012) acids and lower molar proportions of propionic acid (P = 0.003). There were no differences between diets for N intake (P = 0.175), fecal N output (P = 0.253), and N balance (P = 0.695), with all sheep in positive N balance; however, there was significantly lower (P = 0.001) urinary N output for sheep-fed Hemp. Cannabidiolic acid (CBDA) and tetrahydrocannabinolic acid (THCA) were detected in plasma of all sheep-fed Hemp. ∆9-tetrahydrocannabinol was present in the subcutaneous fat of four of the six sheep on the final day of being fed Hemp, and in all (six) sheep 35 d post-feeding and one sheep 140 d post-feeding Hemp. No cannabinoids were detected in the corresponding samples taken from the sheep-fed Control. Thus, despite green hemp biomass being nutritionally a suitable feed for ruminants, under current Food Standards in Australia, the presence of these cannabinoid residues restricts its use in ruminant diets.

10.
Sci Rep ; 10(1): 3545, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32103114

RESUMO

A field study was conducted on smallholder farmer fields between 2012 to 2014 to evaluate the performance of cv. Agaitti Berseem-2002, against local landraces exchanged between farmers (LBF1) or available from local markets (LBM1). The effects of genotype and harvesting regimen on forage production, quality and seed production were evaluated. Significant differences (P < 0.05) among genotypes and cutting treatments were recorded for forage and seed yields, and forage quality across all research sites in both years. Maximum cumulative fresh forage (89.7 t/ha) and dry matter (DM; 13.4 t/ha) yields were obtained with Agaitti Berseem-2002 when harvesting occurred five times over the season. However, maximum seed yield (1048 kg/ha) with higher 1000-seed weight (3.63 g) were obtained if forage was only harvested three times and the crop then left for seed set. Agaitti Berseem-2002 also produced forage with the higher crude protein content (27%), DM digestibility (69%), digestible organic matter (DM basis; 65%) and metabolizable energy content (10%) compared to the local landraces (LBF1 and LBM1). Therefore, the harvesting regimen for greatest economic return which produced optimum fresh and DM forage yields of highest nutritive values and maximum seed yield, were comprised of taking three forage cuts (at 65, 110 and 150 days after sowing) prior to seed harvest.


Assuntos
Pesquisa Participativa Baseada na Comunidade , Produção Agrícola , Fazendeiros , Fazendas , Genótipo , Medicago/crescimento & desenvolvimento , Medicago/genética , Paquistão , Estações do Ano
11.
Eur Psychiatry ; 56: 35-42, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30496954

RESUMO

BACKGROUND: Punitive parenting and stressful life events are associated with obsessive-compulsive symptoms (OCS). However, the lack of longitudinal, genetically-informative studies means it remains unclear whether these factors represent environmentally-mediated risks for the development of OCS. METHODS: Twins and siblings from the Genesis1219 study completed self-report questionnaires two years apart (Time 1: N = 2616, mean age = 15.0; Time 2: N = 1579, mean age = 17.0 years) assessing OCS, maternal and paternal punitive parenting, and dependent stressful life events. Multiple regression models tested cross-sectional and longitudinal associations between the putative environmental risk factors and obsessive-compulsive symptoms using: (a) individual scores; and (b) monozygotic twin difference scores. The aetiologies of significant phenotypic associations between putative risk factors and OCS were further examined using multivariate genetic models. RESULTS: At a phenotypic level, maternal and paternal punitive parenting and stressful life events were all associated with OCS both cross-sectionally and longitudinally. However, only stressful life events predicted the subsequent development of OCS, after controlling for earlier symptoms. Genetic models indicated that the association between life events and change in OCS symptoms was due to both genetic (48%) and environmental (52%) influences. Overall, life events associated with change in OCS accounted for 1.2% of variation in OCS at Time 2. CONCLUSIONS: Stressful life events, but not punitive parenting, predict OCS change during adolescence at a phenotypic level. This association exists above and beyond genetic confounding, consistent with the hypothesis that stressful life events play a causal role in the development of obsessive-compulsive symptoms.


Assuntos
Doenças em Gêmeos/epidemiologia , Transtorno Obsessivo-Compulsivo/epidemiologia , Irmãos/psicologia , Estresse Psicológico/epidemiologia , Gêmeos/estatística & dados numéricos , Adolescente , Adulto , Comorbidade , Estudos Transversais , Doenças em Gêmeos/psicologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Transtorno Obsessivo-Compulsivo/psicologia , Poder Familiar , Fatores de Risco , Autorrelato , Estresse Psicológico/psicologia , Inquéritos e Questionários , Gêmeos/psicologia
12.
Aust Vet J ; 95(6): 211-216, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28555954

RESUMO

OBJECTIVES: To examine the prevalence of Theileria orientalis in the Gloucester area of New South Wales and its effect on individual animals. METHODS: Blood samples (EDTA and clotted blood) were collected from a total of 55 calves and their dams from 6 properties over a 16-week period. A total of 202 and 190 blood samples were collected from the calves and dams, respectively, and were examined via blood film for the presence of intraerythrocytic T. orientalis piroplasms. Packed cell volume (PCV) was measured to determine infection resulting in anaemia. The presence of antibodies against the T. orientalis major piroplasm surface protein (MPSP) was tested using ELISA. RESULTS: The overall prevalence of T. orientalis infection in both dams and calves from all herds examined was 95%. Mean peak parasitaemia was observed in calves between 6 and 9 weeks of age (P = 0.051), coinciding with a decline in mean PCV. Only 3 (6%) of the blood samples collected from the dams were positive for Theileria-associated antibodies and no significant relationship (P > 0.05) was found between the presence of antibodies in the dams and PCV levels in the calves. There was no evidence that passive transfer of antibodies from dams to calves protected the calves against a decline in PCV. CONCLUSION: This study confirmed a high prevalence of low-level Theileria infection, but low MPSP seroconversion rates, in dams and calves in an area where the disease has been endemic for a number of years.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Theileriose/epidemiologia , Anemia/epidemiologia , Anemia/parasitologia , Anemia/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Bovinos , Doenças dos Bovinos/sangue , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Masculino , Merozoítos , New South Wales/epidemiologia , Reação em Cadeia da Polimerase/veterinária , Prevalência , Theileria/genética , Theileria/imunologia , Theileriose/sangue , Theileriose/complicações
13.
Biochim Biophys Acta ; 854(2): 184-90, 1986 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-3942723

RESUMO

Plasma membrane vesicles from calf T-lymphocytes were fractionated by affinity chromatography on Con A-Sepharose. One subfraction eluted freely from the affinity column (fraction 1), while a second one adhered specifically to the column (fraction 2). While both fractions were derived exclusively from the plasma membrane, fraction 2 carried the high-affinity receptor for the mitogen concanavalin A and was distinct from fraction 1 with respect to its polypeptide pattern and the content of some plasma membrane-associated enzymes, suggesting the existence of functional plasma membrane domains. These functionally distinct fractions showed different lipid composition. The adherent fraction was enriched in phosphatidylcholine, while the relative amount of phosphatidylethanolamine and phosphatidylserine was reduced. Furthermore, the relative amount of saturated fatty acids was enhanced in the phospholipids of the adherent plasma membrane fraction. This could be shown in total phospholipids, as well as in separated individual phospholipids. We could therefore demonstrate that lipid heterogeneity may exist in plasma membranes of cells without structural polarity. Similar results were obtained when T-lymphocytes were stimulated with the mitogen concanavalin A. The functional domain, consisting of the high-affinity concanavalin A receptor, several enzymes and distinct lipid compositional pattern, thus seems to constitute a relatively stable structural entity of the lymphocyte plasma membrane.


Assuntos
Linfócitos/citologia , Lipídeos de Membrana/análise , 1-Acilglicerofosfocolina O-Aciltransferase/metabolismo , Animais , Bovinos , Cromatografia de Afinidade , Ácidos Graxos/análise , Fosfatidilcolinas/análise , Fosfatidiletanolaminas/análise
14.
Biochim Biophys Acta ; 732(3): 675-82, 1983 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-6871220

RESUMO

To study the interaction of voltage-sensitive Na+-channels with membrane lipids, the phospholipid and fatty acid composition of highly purified membrane fragments from the remarkably differentiated plasma membrane of Electrophorus electricus has been analyzed. After density gradient fractionation and carrier free electrophoresis, fractions with up to 30 pmol tetrodotoxin binding/mg protein can be obtained, which may correspond to a 50% pure preparation of the extrasynaptic part of the excitable face. Phospholipid classes and cholesterol are separated by one-dimensional thin-layer chromatography in acidic and alkaline solvent systems. The following mean molar contents are found: 40% phosphatidylcholine, 23% phosphatidylserine, 30% phosphatidylethanolamine and 7% sphingomyelin. In a series of 11 animals, significant deviations from these mean values have been observed. The fatty acid composition of the phospholipids has been determined by gas chromatography. Phosphatidylcholine contains more than 50% 16:0, and about 20% unsaturated fatty acids in the C-18 group. Compared to other plasma membrane fractions, this phospholipid is the least differentiated. By contrast, phosphatidylethanolamine and phosphatidylserine show many characteristics in different membrane fractions, especially in their unsaturated components representing more than 50%. 22:6, as the major constituent in these fractions, accounts for a quarter to a third of all fatty acids in these fractions. 18:0 is the main saturated component in these two phospholipids with abundances of typically a quarter or less of all fatty acids. Knowledge of the lipid composition of these excitable membranes may help to conserve binding and structural properties when analyzing lipid-sensitive Na+-channels in vitro. It is also useful as a guideline for systematic reconstitution studies.


Assuntos
Proteínas de Transporte/isolamento & purificação , Ácidos Graxos/análise , Lipídeos de Membrana/análise , Fosfolipídeos/análise , Canais de Sódio , Tetrodotoxina/isolamento & purificação , Animais , Membrana Celular/análise , Colesterol/análise , Órgão Elétrico/análise , Electrophorus , Relação Estrutura-Atividade
15.
Aust Vet J ; 93(1-2): 26-30, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25622705

RESUMO

OBJECTIVES: To investigate the accuracy of both the optical and digital Brix refractometers compared with radial immunodiffusion (RID) for determining the immunoglobulin G (IgG) concentrations in dairy calf serum. DESIGN: The experiment design was a cross-sectional survey of four dairy farms. Serum was sampled from 12 calves from each farm at approximately 48 hours of age. METHODS: Serum IgG concentrations of 48 calves were measured using RID and both types of Brix refractometer. RESULTS: IgG concentrations measured by Brix refractometer scores correlated with RID results: 0.74 and 0.71 for the digital and optical devices, respectively. The minimum Brix score that identified calf serum with success of passive immunity (>1000 mg/dL RID IgG) with 100% accuracy was 10% for both devices. The optical and digital devices performed similarly at identifying IgG concentrations in calf serum, with a concordance of 87%. CONCLUSION: Brix refractometer score ≥10% can be used to classify calves with successful transfer of passive immunity and the devices are sufficiently accurate for use as a simple, inexpensive on-farm tool for the monitoring of neonatal dairy calf immunity levels.


Assuntos
Animais Recém-Nascidos/imunologia , Bovinos/imunologia , Imunidade Materno-Adquirida , Refratometria/veterinária , Animais , Colostro/imunologia , Estudos Transversais , Indústria de Laticínios , Imunoglobulina G/sangue , Modelos Lineares , New South Wales , Refratometria/métodos , Reprodutibilidade dos Testes
16.
Aust Vet J ; 93(6): 208-13, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26010927

RESUMO

CASE REPORT: This report documents an outbreak of acute renal failure in a flock of 9-month-old White Suffolk-cross ewe lambs. The mortality rate was moderate but the morbidity was high. The lambs had grazed a wheat stubble paddock in which there were several weed species, including Amaranthus spp. CLINICAL SIGNIFICANCE: Renal failure in livestock has been reported internationally following the ingestion of Amaranthus spp. and although it has previously been suspected in Australia no cases have been documented. It is important for Australian veterinarians and farmers to realise the toxic potential of this group of plants.


Assuntos
Injúria Renal Aguda/veterinária , Amaranthus/intoxicação , Intoxicação por Plantas/complicações , Doenças dos Ovinos/etiologia , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/patologia , Animais , Surtos de Doenças/veterinária , Rim/patologia , New South Wales/epidemiologia , Intoxicação por Plantas/etiologia , Intoxicação por Plantas/patologia , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/patologia
17.
J Abnorm Child Psychol ; 43(5): 933-42, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25301176

RESUMO

Depression frequently co-occurs with paediatric obsessive-compulsive disorder (OCD), yet the clinical correlates and impact of depression on CBT outcomes remain unclear. The prevalence and clinical correlates of depression were examined in a paediatric specialist OCD-clinic sample (N = 295; Mean = 15 [7 - 18] years, 42 % female), using both dimensional (Beck Depression Inventory-youth; n = 261) and diagnostic (Development and Wellbeing Assessment; n = 127) measures of depression. The impact of depressive symptoms and suspected disorders on post-treatment OCD severity was examined in a sub-sample who received CBT, with or without SSRI medication (N = 100). Fifty-one per-cent of patients reported moderately or extremely elevated depressive symptoms and 26 % (95 % CI: 18 - 34) met criteria for a suspected depressive disorder. Depressive symptoms and depressive disorders were associated with worse OCD symptom severity and global functioning prior to CBT. Individuals with depression were more likely to be female, have had a psychiatric inpatient admission and less likely to be attending school (ps < 0.01). OCD and depressive symptom severity significantly decreased after CBT. Depressive symptoms and depressive disorders predicted worse post-treatment OCD severity (ßs = 0.19 and 0.26, ps < 0.05) but became non-significant when controlling for pre-treatment OCD severity (ßs = 0.05 and 0.13, ns). Depression is common in paediatric OCD and is associated with more severe OCD and poorer functioning. However, depression severity decreases over the course of CBT for OCD and is not independently associated with worse outcomes, supporting the recommendation for treatment as usual in the presence of depressive symptoms.


Assuntos
Terapia Cognitivo-Comportamental , Depressão/psicologia , Transtorno Obsessivo-Compulsivo/psicologia , Adolescente , Criança , Comorbidade , Depressão/diagnóstico , Depressão/epidemiologia , Depressão/terapia , Feminino , Humanos , Masculino , Transtorno Obsessivo-Compulsivo/diagnóstico , Transtorno Obsessivo-Compulsivo/epidemiologia , Transtorno Obsessivo-Compulsivo/terapia , Prevalência , Escalas de Graduação Psiquiátrica , Índice de Gravidade de Doença , Resultado do Tratamento
18.
J Behav Ther Exp Psychiatry ; 48: 75-81, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25753746

RESUMO

BACKGROUND AND OBJECTIVES: Transformation obsessions denote an under-reported symptom of Obsessive Compulsive Disorder (OCD), characterised by an excessive fear of turning into another person/object or acquiring unwanted characteristics. Relative to other OCD symptoms, little is known about the clinical presentation of transformation obsessions. The study aims to examine the clinical correlates and treatment prognosis of transformation obsessions in a paediatric OCD sample. METHODS: The sample consisted of 346 youths with a primary diagnosis of OCD. Patients with and without transformation obsessions were compared in terms of demographic and clinical characteristics, and CBT outcomes. RESULTS: 10% of the sample endorsed transformation obsessions. Patients with transformation obsessions were more likely to be boys, to be on augmented medication regimes, and to present with more severe obsessions at assessment. A factor analysis identified four major OCD symptom clusters, with transformation obsessions loading on a 'forbidden thoughts' factor alongside aggressive, sexual, and religious obsessions. No group differences in treatment outcomes were observed. LIMITATIONS: Limitations include the cross-sectional and retrospective nature of the study, the representativeness of our sample, and use of concomitant medication, among others. CONCLUSIONS: The study provides the first empirical evidence regarding phenomenological similarities and differences between paediatric OCD patients presenting with and without transformation obsessions. The findings suggest that transformation obsessions are best conceptualised as related to 'forbidden' obsessions and respond to exposure-based CBT.


Assuntos
Terapia Cognitivo-Comportamental/métodos , Transtorno Obsessivo-Compulsivo/fisiopatologia , Transtorno Obsessivo-Compulsivo/terapia , Adolescente , Criança , Feminino , Humanos , Masculino , Fatores Sexuais , Resultado do Tratamento
19.
Biochimie ; 61(4): 559-65, 1979.
Artigo em Francês | MEDLINE | ID: mdl-90529

RESUMO

The complex formed between trypsin (Tn) and alpha 2 Macroglobulin (alpha 2 M) retains the whole hydrolytic activity of the enzyme for synthetic substrates. Moreover synthetic inhibitors of low molecular weight stiel inhibit this activity. A comparative study of three inhibitors (Benzylamine, Butylamine, Benzamidine) has been carried out and shows that their behavior is similar. These inhibitors bind trypsin when it is bound to alpha 2 M and reciprocally alpha 2 M can bind Tn-inhibitor complex. Nevertheless the dissociation constant of the enzyme-inhibitor complex (Ki) is increased by alpha 2 M. In the case of Benzamidine the value of Ki is 2.22.10(-5) M for native enzyme and 13.4.10(-5) M for Tn-alpha 2 M and in the case of Butylamine this value increases from 0.5.10(-3) M to 2.95.10(-3) M. These variations of the Ki values are due to the modification of the accessibility of the inhibitor to the active site. Unpublished results show that the alpha 2 M molecule undergoes a deep structural modification in the course of the complex formation, which must lead to an increase of the value of Ki. This structural modification is probably irreversible so that the alpha 2 M complex has never been dissociated without altering the alpha 2 M molecule. The increase of the values of Ki cannot therefore result in an effective decrease of the association constant of the Tn-alpha 2 M complex.


Assuntos
Inibidores da Tripsina/farmacologia , Tripsina/metabolismo , alfa-Macroglobulinas/metabolismo , Sítios de Ligação , Cinética
20.
Behav Brain Res ; 80(1-2): 65-73, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8905130

RESUMO

The thalamofugal visual projections of the chick are known to develop in response to stimulation by light prior to hatching, and asymmetry in the number of projections develops as a consequence of the embryo being oriented in the egg so that it occuludes its left eye. The right eye only is stimulated by light and this causes the visual projections connected to the right eye to develop in advance of those connected to the left. We have now found that exposure of embryos, from day 19 of incubation to hatching, to red (peak transmission at 670 nm) or green (peak at 500 nm) light is as effective as broad-spectrum (white) light in establishing asymmetry in these projections. The intensities of the light to which the embryos were exposed in each case were equivalent, achieved in part by removing the air sac end of the egg shell. The thalamofugal visual projections, therefore, develop in response to light stimulation but appear to have no wavelength specificity. This result is consistent with the apparent lack of involvement of the thalamofugal visual pathway in colour vision. However, functional asymmetry, tested as left-right eye differences in categorising grain from pebbles, was found to be less marked in the chicks that had been exposed to green light compared to those that had been exposed to 'while' light, and it was absent in those exposed to red light or incubated in the dark. Thus, there is wavelength specificity for the development of the behavioural asymmetry, which suggests involvement of colour-coded neurons outside the thalamofugal visual pathway, probably in the tectofugal pathway. Exposure of the embryos to red and green light alternating at 30 min intervals is as effective as "white' light for establishing both the structural and functional asymmetry.


Assuntos
Lateralidade Funcional/efeitos da radiação , Prosencéfalo/embriologia , Prosencéfalo/efeitos da radiação , Tálamo/embriologia , Tálamo/efeitos da radiação , Vias Visuais/embriologia , Vias Visuais/efeitos da radiação , Animais , Embrião de Galinha , Cor , Corantes Fluorescentes , Luz , Técnicas Estereotáxicas
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