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1.
Mol Psychiatry ; 23(5): 1169-1180, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29155802

RESUMO

Anorexia nervosa (AN) is a complex neuropsychiatric disorder presenting with dangerously low body weight, and a deep and persistent fear of gaining weight. To date, only one genome-wide significant locus associated with AN has been identified. We performed an exome-chip based genome-wide association studies (GWAS) in 2158 cases from nine populations of European origin and 15 485 ancestrally matched controls. Unlike previous studies, this GWAS also probed association in low-frequency and rare variants. Sixteen independent variants were taken forward for in silico and de novo replication (11 common and 5 rare). No findings reached genome-wide significance. Two notable common variants were identified: rs10791286, an intronic variant in OPCML (P=9.89 × 10-6), and rs7700147, an intergenic variant (P=2.93 × 10-5). No low-frequency variant associations were identified at genome-wide significance, although the study was well-powered to detect low-frequency variants with large effect sizes, suggesting that there may be no AN loci in this genomic search space with large effect sizes.


Assuntos
Anorexia Nervosa/genética , Moléculas de Adesão Celular/genética , Exoma/genética , Família , Feminino , Proteínas Ligadas por GPI/genética , Predisposição Genética para Doença/genética , Variação Genética/genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Íntrons/genética , Masculino , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , População Branca/genética
3.
Psychol Med ; 48(1): 82-94, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28545597

RESUMO

BACKGROUND: Our understanding of the complex relationship between schizophrenia symptomatology and etiological factors can be improved by studying brain-based correlates of schizophrenia. Research showed that impairments in value processing and executive functioning, which have been associated with prefrontal brain areas [particularly the medial orbitofrontal cortex (MOFC)], are linked to negative symptoms. Here we tested the hypothesis that MOFC thickness is associated with negative symptom severity. METHODS: This study included 1985 individuals with schizophrenia from 17 research groups around the world contributing to the ENIGMA Schizophrenia Working Group. Cortical thickness values were obtained from T1-weighted structural brain scans using FreeSurfer. A meta-analysis across sites was conducted over effect sizes from a model predicting cortical thickness by negative symptom score (harmonized Scale for the Assessment of Negative Symptoms or Positive and Negative Syndrome Scale scores). RESULTS: Meta-analytical results showed that left, but not right, MOFC thickness was significantly associated with negative symptom severity (ß std = -0.075; p = 0.019) after accounting for age, gender, and site. This effect remained significant (p = 0.036) in a model including overall illness severity. Covarying for duration of illness, age of onset, antipsychotic medication or handedness weakened the association of negative symptoms with left MOFC thickness. As part of a secondary analysis including 10 other prefrontal regions further associations in the left lateral orbitofrontal gyrus and pars opercularis emerged. CONCLUSIONS: Using an unusually large cohort and a meta-analytical approach, our findings point towards a link between prefrontal thinning and negative symptom severity in schizophrenia. This finding provides further insight into the relationship between structural brain abnormalities and negative symptoms in schizophrenia.


Assuntos
Córtex Pré-Frontal/patologia , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/patologia , Adulto , Feminino , Lateralidade Funcional , Humanos , Processamento de Imagem Assistida por Computador , Internacionalidade , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Escalas de Graduação Psiquiátrica , Psicologia do Esquizofrênico
4.
Mol Psychiatry ; 22(2): 250-256, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27217153

RESUMO

Attention-deficit/hyperactivity disorder (ADHD) is a prevalent developmental disorder, associated with a range of long-term impairments. Variation in DNA methylation, an epigenetic mechanism, is implicated in both neurobiological functioning and psychiatric health. However, the potential role of DNA methylation in ADHD symptoms is currently unclear. In this study, we examined data from the Avon Longitudinal Study of Parents and Children (ALSPAC)-specifically the subsample forming the Accessible Resource for Integrated Epigenomics Studies (ARIES)-that includes (1) peripheral measures of DNA methylation (Illumina 450k) at birth (n=817, 49% male) and age 7 (n=892, 50% male) and (2) trajectories of ADHD symptoms (7-15 years). We first employed a genome-wide analysis to test whether DNA methylation at birth associates with later ADHD trajectories; and then followed up at age 7 to investigate the stability of associations across early childhood. We found that DNA methylation at birth differentiated ADHD trajectories across multiple genomic locations, including probes annotated to SKI (involved in neural tube development), ZNF544 (previously implicated in ADHD), ST3GAL3 (linked to intellectual disability) and PEX2 (related to perixosomal processes). None of these probes maintained an association with ADHD trajectories at age 7. Findings lend novel insights into the epigenetic landscape of ADHD symptoms, highlighting the potential importance of DNA methylation variation in genes related to neurodevelopmental and peroxisomal processes that play a key role in the maturation and stability of cortical circuits.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/genética , Metilação de DNA/genética , Adolescente , Criança , Impressões Digitais de DNA/métodos , Epigênese Genética/genética , Epigenômica/métodos , Feminino , Humanos , Recém-Nascido , Estudos Longitudinais , Masculino , Estudos Prospectivos
5.
Mol Psychiatry ; 21(4): 547-53, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26033243

RESUMO

The profile of brain structural abnormalities in schizophrenia is still not fully understood, despite decades of research using brain scans. To validate a prospective meta-analysis approach to analyzing multicenter neuroimaging data, we analyzed brain MRI scans from 2028 schizophrenia patients and 2540 healthy controls, assessed with standardized methods at 15 centers worldwide. We identified subcortical brain volumes that differentiated patients from controls, and ranked them according to their effect sizes. Compared with healthy controls, patients with schizophrenia had smaller hippocampus (Cohen's d=-0.46), amygdala (d=-0.31), thalamus (d=-0.31), accumbens (d=-0.25) and intracranial volumes (d=-0.12), as well as larger pallidum (d=0.21) and lateral ventricle volumes (d=0.37). Putamen and pallidum volume augmentations were positively associated with duration of illness and hippocampal deficits scaled with the proportion of unmedicated patients. Worldwide cooperative analyses of brain imaging data support a profile of subcortical abnormalities in schizophrenia, which is consistent with that based on traditional meta-analytic approaches. This first ENIGMA Schizophrenia Working Group study validates that collaborative data analyses can readily be used across brain phenotypes and disorders and encourages analysis and data sharing efforts to further our understanding of severe mental illness.


Assuntos
Encéfalo/patologia , Esquizofrenia/patologia , Adulto , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Estudos de Casos e Controles , Feminino , Lateralidade Funcional , Humanos , Processamento de Imagem Assistida por Computador , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem , Estudos Prospectivos , Esquizofrenia/genética
6.
Acta Psychiatr Scand ; 135(5): 439-447, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28369804

RESUMO

OBJECTIVE: Based on the role of the superior temporal gyrus (STG) in auditory processing, language comprehension and self-monitoring, this study aimed to investigate the relationship between STG cortical thickness and positive symptom severity in schizophrenia. METHOD: This prospective meta-analysis includes data from 1987 individuals with schizophrenia collected at seventeen centres around the world that contribute to the ENIGMA Schizophrenia Working Group. STG thickness measures were extracted from T1-weighted brain scans using FreeSurfer. The study performed a meta-analysis of effect sizes across sites generated by a model predicting left or right STG thickness with a positive symptom severity score (harmonized SAPS or PANSS-positive scores), while controlling for age, sex and site. Secondary models investigated relationships between antipsychotic medication, duration of illness, overall illness severity, handedness and STG thickness. RESULTS: Positive symptom severity was negatively related to STG thickness in both hemispheres (left: ßstd = -0.052; P = 0.021; right: ßstd = -0.073; P = 0.001) when statistically controlling for age, sex and site. This effect remained stable in models including duration of illness, antipsychotic medication or handedness. CONCLUSION: Our findings further underline the important role of the STG in hallmark symptoms in schizophrenia. These findings can assist in advancing insight into symptom-relevant pathophysiological mechanisms in schizophrenia.


Assuntos
Imageamento por Ressonância Magnética/métodos , Esquizofrenia/diagnóstico por imagem , Lobo Temporal/diagnóstico por imagem , Adulto , Mapeamento Encefálico/métodos , Feminino , Humanos , Masculino , Estudos Prospectivos , Escalas de Graduação Psiquiátrica , Esquizofrenia/patologia , Psicologia do Esquizofrênico , Lobo Temporal/patologia
7.
medRxiv ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39006433

RESUMO

Background: Autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), and schizophrenia (SCZ) are highly heritable and linked to disruptions in foetal (neuro)development. While epigenetic processes are considered an important underlying pathway between genetic susceptibility and neurodevelopmental conditions, it is unclear (i) whether genetic susceptibility to these conditions is associated with epigenetic patterns, specifically DNA methylation (DNAm), already at birth; (ii) to what extent DNAm patterns are unique or shared across conditions, and (iii) whether these neonatal DNAm patterns can be leveraged to enhance genetic prediction of (neuro)developmental outcomes. Methods: We conducted epigenome-wide meta-analyses of genetic susceptibility to ASD, ADHD, and schizophrenia, quantified using polygenic scores (PGSs) on cord blood DNAm, using four population-based cohorts (n pooled=5,802), all North European. Heterogeneity statistics were used to estimate overlap in DNAm patterns between PGSs. Subsequently, DNAm-based measures of PGSs were built in a target sample, and used as predictors to test incremental variance explained over PGS in 130 (neuro)developmental outcomes spanning birth to 14 years. Outcomes: In probe-level analyses, SCZ-PGS associated with neonatal DNAm at 246 loci (p<9×10-8), predominantly in the major histocompatibility complex. Functional characterization of these DNAm loci confirmed strong genetic effects, significant blood-brain concordance and enrichment for immune-related pathways. 8 loci were identified for ASD-PGS (mapping to FDFT1 and MFHAS1), and none for ADHD-PGS. Regional analyses indicated a large number of differentially methylated regions for all PGSs (SCZ-PGS: 157, ASD-PGS: 130, ADHD-PGS: 166). DNAm signals showed little overlap between PGSs. We found suggestive evidence that incorporating DNAm-based measures of genetic susceptibility at birth increases explained variance for several child cognitive and motor outcomes over and above PGS. Interpretation: Genetic susceptibility for neurodevelopmental conditions, particularly schizophrenia, is detectable in cord blood DNAm at birth in a population-based sample, with largely distinct DNAm patterns between PGSs. These findings support an early-origins perspective on schizophrenia. Funding: HorizonEurope; European Research Council.

8.
Int J Clin Health Psychol ; 24(2): 100458, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38623146

RESUMO

Background/Objective. Enlarged lateral ventricle (LV) volume and decreased volume in the corpus callosum (CC) are hallmarks of schizophrenia (SZ). We previously showed an inverse correlation between LV and CC volumes in SZ, with global functioning decreasing with increased LV volume. This study investigates the relationship between LV volume, CC abnormalities, and the microRNA MIR137 and its regulated genes in SZ, because of MIR137's essential role in neurodevelopment. Methods. Participants were 1224 SZ probands and 1466 unaffected controls from the GENUS Consortium. Brain MRI scans, genotype, and clinical data were harmonized across cohorts and employed in the analyses. Results. Increased LV volumes and decreased CC central, mid-anterior, and mid-posterior volumes were observed in SZ probands. The MIR137-regulated ephrin pathway was significantly associated with CC:LV ratio, explaining a significant proportion (3.42 %) of CC:LV variance, and more than for LV and CC separately. Other pathways explained variance in either CC or LV, but not both. CC:LV ratio was also positively correlated with Global Assessment of Functioning, supporting previous subsample findings. SNP-based heritability estimates were higher for CC central:LV ratio (0.79) compared to CC or LV separately. Discussion. Our results indicate that the CC:LV ratio is highly heritable, influenced in part by variation in the MIR137-regulated ephrin pathway. Findings suggest that the CC:LV ratio may be a risk indicator in SZ that correlates with global functioning.

9.
Radiography (Lond) ; 29(3): 519-525, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36907026

RESUMO

OBJECTIVES: The objectives of this work were first to examine referral practices from primary care for MRI knee in patients ≥45 years old and then to develop a new referral pathway to reduce the number of inappropriate MRI knee referrals. Following this, the aim was to re-assess the effect of the intervention and identify further areas for improvement. METHODS: A baseline retrospective analysis of knee MRIs requested from primary care in symptomatic patients ≥45years over a two-month period was undertaken. A new referral pathway was implemented in consensus with orthopaedic specialists and the clinical commissioning group (CCG), via the CCG resource webpage and local education. Following implementation, a repeat data analysis was undertaken. RESULTS: The number of MRI knees acquired from primary care referrals reduced by 42% after the new pathway was implemented. 67% (46/69) were compliant with the new guidelines. The number of patients having an MRI knee without a prior plain radiograph was 14/69 (20%) compared to 55/118 (47%) prior the pathway changes. CONCLUSION: The new referral pathway reduced the number of knee MRI acquisitions in primary care patients ≥45 years by 42%. Changing the pathway has decreased the number of patients undergoing MRI knee without a prior radiograph from 47% to 20%. These outcomes bring our standards towards the evidence-based recommendations of the Royal College of Radiology and have reduced our outpatient waiting list for MRI knee. IMPLICATIONS FOR PRACTICE: Implementing a new referral pathway with the local CCG can successfully reduce the number of inappropriate MRI knee acquisitions from primary care referrals in older symptomatic patients.


Assuntos
Imageamento por Ressonância Magnética , Melhoria de Qualidade , Humanos , Idoso , Pessoa de Meia-Idade , Estudos Retrospectivos , Encaminhamento e Consulta , Atenção Primária à Saúde
11.
Psychol Med ; 40(1): 51-61, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19460189

RESUMO

BACKGROUND: This study examined whether there were associations between individual measures of socio-economic status (SES) and the 12-month prevalence of major depressive disorder (MDD) in representative samples of Blacks, Latinos, Asians and Whites in the USA. METHOD: The data used were from the Collaborative Psychiatric Epidemiology Studies (CPES). RESULTS: There was an association between household income and MDD among Whites. However, the association was not statistically significant. Statistically significant associations were present between educational attainment and MDD among Whites. Among both Whites and Latinos, being out of the labor force was significantly associated with MDD. In analyses by nativity, being out of the labor force was significantly associated with MDD among US-born and foreign-born Latinos. CONCLUSIONS: Significant associations between various measures of SES and MDD were consistently observed among White and, in some cases, Latino populations. Future studies should continue to examine sociopsychological factors related to SES that increase the risk of MDD among people from racial-ethnic communities.


Assuntos
Asiático/psicologia , População Negra/psicologia , Transtorno Depressivo Maior/etnologia , Emigrantes e Imigrantes/psicologia , Hispânico ou Latino/psicologia , Fatores Socioeconômicos , População Branca/psicologia , Adulto , Asiático/estatística & dados numéricos , População Negra/estatística & dados numéricos , Estudos Transversais , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/epidemiologia , Transtorno Depressivo Maior/psicologia , Emigrantes e Imigrantes/estatística & dados numéricos , Feminino , Inquéritos Epidemiológicos , Hispânico ou Latino/estatística & dados numéricos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estados Unidos , População Branca/estatística & dados numéricos
12.
Science ; 253(5021): 789-92, 1991 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-1876836

RESUMO

Recombinant cDNA clones that encode two distinct subunits of the transcription factor GA binding protein (GABP) have been isolated. The predicted amino acid sequence of one subunit, GABP alpha, exhibits similarity to the sequence of the product of the ets-1 protooncogene in a region known to encompass the Ets DNA binding domain. The sequence of the second subunit, GABP beta, contains four 33-amino acid repeats located close to the NH2-terminus of the subunit. The sequences of these repeats are similar to repeats in several transmembrane proteins, including Notch from Drosophila melanogaster and Glp-1 and Lin-12 from Caenorhabditis elegans. Avid, sequence-specific binding to DNA required the presence of both polypeptides, revealing a conceptual convergence of nuclear transforming proteins and membrane-anchored proteins implicated in developmentally regulated signal transduction processes.


Assuntos
Proteínas de Ligação a DNA/química , Fatores de Transcrição/química , Sequência de Aminoácidos , Animais , Northern Blotting , Clonagem Molecular , Proteínas de Ligação a DNA/genética , Fator de Transcrição de Proteínas de Ligação GA , Expressão Gênica , Dados de Sequência Molecular , Proteínas Nucleares/química , Proteínas Nucleares/genética , Peptídeos/química , Proteína Proto-Oncogênica c-ets-1 , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas c-ets , RNA Mensageiro/genética , Ratos , Proteínas Recombinantes , Fatores de Transcrição/genética
13.
Inj Prev ; 15(6): 413-7, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19959735

RESUMO

OBJECTIVE: To describe injury patterns at overnight summer camps in 2006, and identify risk factors for more significant injury. DESIGN: Surveillance data obtained from Healthy Camp Study from 2006 were analyzed from 71 overnight camps, representing 437,541 camper-days and 206,031 staff-days. RESULTS: Injuries were reported in 218 campers and 81 staff. 51.8% of injured campers were male versus 34.6% of staff. Among campers, 60.1% were evaluated off-site; 2.3% required hospital admission. 43.9% of injuries required >24 h activity restriction (deemed "significant injury"). Among campers, significant injury was associated with camp sessions > or =14 days (RR 1.48); among staff, with male sex (RR 1.85) and camper-to-staff ratio (RR 0.67). There were no associations with age, time of day, setting, or level of supervision. CONCLUSIONS: Significant injuries are uncommon at overnight summer camps. Rates appear similar to those in comparable activities. Targeted interventions may further reduce injury risk.


Assuntos
Acampamento/estatística & dados numéricos , Ferimentos e Lesões/epidemiologia , Adolescente , Canadá/epidemiologia , Criança , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Periodicidade , Fatores de Risco , Fatores Sexuais , Índices de Gravidade do Trauma , Estados Unidos/epidemiologia , Ferimentos e Lesões/prevenção & controle , Adulto Jovem
14.
Mol Neurobiol ; 56(7): 5146-5156, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30519816

RESUMO

In MRI scans of patients with anorexia nervosa (AN), reductions in brain volume are often apparent. However, it is unknown whether such brain abnormalities are influenced by genetic determinants that partially overlap with those underlying AN. Here, we used a battery of methods (LD score regression, genetic risk scores, sign test, SNP effect concordance analysis, and Mendelian randomization) to investigate the genetic covariation between subcortical brain volumes and risk for AN based on summary measures retrieved from genome-wide association studies of regional brain volumes (ENIGMA consortium, n = 13,170) and genetic risk for AN (PGC-ED consortium, n = 14,477). Genetic correlations ranged from - 0.10 to 0.23 (all p > 0.05). There were some signs of an inverse concordance between greater thalamus volume and risk for AN (permuted p = 0.009, 95% CI: [0.005, 0.017]). A genetic variant in the vicinity of ZW10, a gene involved in cell division, and neurotransmitter and immune system relevant genes, in particular DRD2, was significantly associated with AN only after conditioning on its association with caudate volume (pFDR = 0.025). Another genetic variant linked to LRRC4C, important in axonal and synaptic development, reached significance after conditioning on hippocampal volume (pFDR = 0.021). In this comprehensive set of analyses and based on the largest available sample sizes to date, there was weak evidence for associations between risk for AN and risk for abnormal subcortical brain volumes at a global level (that is, common variant genetic architecture), but suggestive evidence for effects of single genetic markers. Highly powered multimodal brain- and disorder-related genome-wide studies are needed to further dissect the shared genetic influences on brain structure and risk for AN.


Assuntos
Anorexia Nervosa/diagnóstico por imagem , Anorexia Nervosa/genética , Encéfalo/diagnóstico por imagem , Estudo de Associação Genômica Ampla/métodos , Análise da Randomização Mendeliana/métodos , Polimorfismo de Nucleotídeo Único/genética , Encéfalo/fisiologia , Estudos de Casos e Controles , Humanos , Desequilíbrio de Ligação/genética , Imageamento por Ressonância Magnética/métodos , Tamanho do Órgão
15.
Transl Psychiatry ; 6(12): e976, 2016 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-27922636

RESUMO

Epigenetic processes have been implicated in addiction; yet, it remains unclear whether these represent a risk factor and/or a consequence of substance use. Here, we believe we conducted the first genome-wide, longitudinal study to investigate whether DNA methylation patterns in early life prospectively associate with substance use in adolescence. The sample comprised of 244 youth (51% female) from the Avon Longitudinal Study of Parents and Children (ALSPAC), with repeated assessments of DNA methylation (Illumina 450k array; cord blood at birth, whole blood at age 7) and substance use (tobacco, alcohol and cannabis use; age 14-18). We found that, at birth, epigenetic variation across a tightly interconnected genetic network (n=65 loci; q<0.05) associated with greater levels of substance use during adolescence, as well as an earlier age of onset amongst users. Associations were specific to the neonatal period and not observed at age 7. Key annotated genes included PACSIN1, NEUROD4 and NTRK2, implicated in neurodevelopmental processes. Several of the identified loci were associated with known methylation quantitative trait loci, and consequently likely to be under significant genetic control. Collectively, these 65 loci were also found to partially mediate the effect of prenatal maternal tobacco smoking on adolescent substance use. Together, findings lend novel insights into epigenetic correlates of substance use, highlight birth as a potentially sensitive window of biological vulnerability and provide preliminary evidence of an indirect epigenetic pathway linking prenatal tobacco exposure and adolescent substance use.


Assuntos
Consumo de Bebidas Alcoólicas/genética , Metilação de DNA , Epigênese Genética/genética , Genoma Humano/genética , Abuso de Maconha/genética , Fumar/genética , Adolescente , Criança , Pré-Escolar , Feminino , Estudo de Associação Genômica Ampla , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Proteínas do Tecido Nervoso/genética , Gravidez , Estudos Prospectivos , Risco
16.
Vet Rec ; 157(20): 613-8, 2005 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-16284329

RESUMO

Four groups of six calves were infected experimentally with either a low dose of approximately 10(4) colony-forming units (cfu) or a high dose of approximately 10(6) cfu of Mycobacterium bovis. Each dose was delivered by the intranasal and intratracheal routes. More severe disease was observed in the groups inoculated with the high dose. Visible lesions were identified in 21 of the 24 animals, all of which also gave positive skin tests and interferon-gamma (IFN-gamma) responses. Nasal shedding was detected in 15 of the 24 animals and the frequency of shedding was influenced by both the route and the dose of infection; no shedding was observed in the group infected intratracheally with the low dose. Two of the 15 confirmed shedders had no visible lesions at postmortem examination; both of these calves gave IFN-gamma responses but only one was skin test positive.


Assuntos
Mycobacterium bovis/patogenicidade , Tuberculose Bovina/microbiologia , Administração Intranasal , Animais , Animais Recém-Nascidos , Bovinos , Contagem de Colônia Microbiana , Ensaio de Imunoadsorção Enzimática/veterinária , Interferon gama/sangue , Mucosa Nasal/microbiologia , Índice de Gravidade de Doença , Testes Cutâneos/veterinária , Traqueia , Tuberculose Bovina/imunologia , Tuberculose Bovina/patologia
17.
Gene ; 165(2): 313-8, 1995 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-8522196

RESUMO

A cDNA encoding human gastric lipase (hGL) has been expressed on multicopy plasmids in the fission yeast Schizosaccharomyces pombe (Sp). Active lipase is secreted from transformants containing the hGL cDNA under the control of either the Sp adh1 promoter (Padh1) or the plant cauliflower mosaic virus (CaMV) 35S promoter. Cell-wall-associated lipase activities are greatest in the early logarithmic growth phase and with Padh1. Western blot analysis indicates that a protein of identical molecular mass to natural hGL is secreted by Sp, although the major secreted product is of a higher molecular mass than either native hGL or recombinant hGL produced in the budding yeast Saccharomyces cerevisiae (Sc). Several distinct hGL are present within cells at all growth phases. Treatment of these proteins with endoglycosidase H gives rise to a single species equivalent in size to deglycosylated natural hGL, indicating that most of these are glycosylation intermediates. An hGL of similar molecular mass accumulates intracellularly in Sp when a modified version of cDNA is used which lacks the sequence encoding the natural secretory signal peptide. Production of hGL markedly slows the growth rate of Sp. The average copy number per cell of the plasmid expressing the hGL cDNA from the recombinant Padh1 is 2-3, as compared with 11-12 for the control plasmid.


Assuntos
Lipase/biossíntese , Lipase/genética , Schizosaccharomyces , Estômago/enzimologia , Álcool Desidrogenase/genética , Caulimovirus/genética , Parede Celular/metabolismo , Dosagem de Genes , Vetores Genéticos/genética , Glicosilação , Hexosaminidases , Humanos , Lipase/química , Lipase/metabolismo , Peso Molecular , Plasmídeos/genética , Regiões Promotoras Genéticas/genética , Sinais Direcionadores de Proteínas/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Schizosaccharomyces/genética , Schizosaccharomyces/crescimento & desenvolvimento , Transformação Genética , Triglicerídeos/metabolismo
18.
Evolution ; 55(9): 1781-94, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11681733

RESUMO

Clonal growth and symbiosis with photosynthetic zooxanthellae typify many genera of marine organisms, suggesting that these traits are usually conserved. However, some, such as Anthopleura, a genus of sea anemones, contain members lacking one or both of these traits. The evolutionary origins of these traits in 13 species of Anthopleura were inferred from a molecular phylogeny derived from 395 bp of the mitochondrial 16S rRNA gene and 410 bp of the mitochondrial cytochrome oxidase subunit III gene. Sequences from these genes were combined and analyzed by maximum-parsimony, maximum-likelihood, and neighbor-joining methods. Best trees from each method indicated a minimum of four changes in growth mode and that symbiosis with zooxanthellae has arisen independently in eastern and western Pacific species. Alternative trees in which species sharing growth modes or the symbiotic condition were constrained to be monophyletic were significantly worse than best trees. Although clade composition was mostly consistent with geographic sympatry, A. artemisia from California was included in the western Pacific clade. Likewise, A. midori from Japan was not placed in a clade containing only other Asian congeners. The history of Anthopleura includes repeated shifts between clonality and solitariness, repeated attainment of symbiosis with zooxanthellae, and intercontinental dispersal.


Assuntos
Evolução Biológica , Anêmonas-do-Mar/fisiologia , Simbiose/genética , Animais , Clonagem de Organismos , Evolução Molecular , Filogenia , RNA Ribossômico 16S/genética , Anêmonas-do-Mar/classificação , Anêmonas-do-Mar/genética
19.
J Med Chem ; 25(4): 457-69, 1982 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7069725

RESUMO

6 beta-[(1-Substituted-4-pyridinio)amino]penam-3-carboxylates and 7 beta-[(1-substituted-4-pyridinio)amino]ceph-3-em-4-carboxylates have been found to be interesting new classes of antibacterial beta-lactams, readily available by SN2 Ar coupling of fluoro-substituted quaternized pyridines and appropriate amino lactam carboxylic acids. Compared to penicillin G, the penam 12c exhibited a spectrum extended to Gram-negative species, such as Escherichia, Shigella, Klebsiella and Enterobacter, offset by a loss of potency against Gram-positive species. Excluding Pseudomonas, many examples of the cephems showed excellent activity against the above Gram-negative organisms, and in some cases, such as 15i, the spectrum included good performance against the staphylococci and streptococci. With Serratia and many Proteus species, there was an adverse inoculum and medium effect which was not observed in the good Gram-positive reach of the cephem series.


Assuntos
Antibacterianos/síntese química , Tienamicinas , Bactérias/efeitos dos fármacos , Fenômenos Químicos , Físico-Química , Espectroscopia de Ressonância Magnética , Relação Estrutura-Atividade , beta-Lactamas/síntese química , beta-Lactamas/farmacologia
20.
J Med Chem ; 29(11): 2298-315, 1986 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3783591

RESUMO

A series of steroids, primarily 4-azasteroids, were prepared and tested in vitro as inhibitors of human and rat prostatic 5 alpha-reductase and of binding of dihydrotestosterone to the rat androgen receptor. The primary structural modifications were changes of the A ring and of moieties attached at the C-17 position of the steroid nucleus. New A-ring modifications included the 4-cyano-3-oxo-delta 4 system in the carbocyclic series and 1 alpha-CN, 1 alpha-CH3, 1 alpha,2 alpha-CH2, 2 beta-F, 2-aza, 2-oxa, and A-homo changes in the 3-oxo-4-aza series. In addition, 4-azasteroids with a D-homo ring or methyl substitution at C-7 (alpha and beta) or C-16 (alpha and beta) were prepared. The majority of the C-17 substituents were prepared from reactive intermediates derived from the 17 beta-COOH. Enhanced 5 alpha-reductase inhibition in both the human and rat enzyme assays is seen with 4-CN substitution on 3-oxo-delta 4 steroids and with a C-17 side chain incorporating a lipophilically substituted semipolar group on the 4-aza-3-oxo-5 alpha-androstane nucleus. Fewer highly active compounds were found in the human enzyme assay than in the rat assay. Structural requirements for inhibition of the rat androgen receptor are much different from those for inhibition of the enzyme. The 17 beta-OH moiety enhances potency more than any other feature while introduction of double bonds at C-1 or C-5 in the azasteroid gives a small improvement. Azasteroids unsubstituted at the 4-position show greatly diminished receptor activity.


Assuntos
Inibidores de 5-alfa Redutase , Azasteroides/síntese química , Receptores Androgênicos/metabolismo , Esteroides Heterocíclicos/síntese química , Animais , Azasteroides/metabolismo , Azasteroides/farmacologia , Humanos , Masculino , Próstata/enzimologia , Ratos , Relação Estrutura-Atividade
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