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1.
Phys Ther Sport ; 42: 75-81, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31951848

RESUMO

OBJECTIVE: To compare foot posture, plantar sensation, plantar fascia thickness, intrinsic foot muscle performance, and abductor hallucis morphology in individuals with and without plantar heel pain (PHP). DESIGN: Cross-Sectional. SETTING: Laboratory. PARTICIPANTS: Sixteen individuals with PHP and sixteen matched healthy participants. MAIN OUTCOME MEASURES: Static foot posture, plantar sensation, plantar fascia thickness, intrinsic foot muscle performance and abductor hallucis morphology were evaluated. Foot posture was assessed with the Foot Posture Index-6. Abductor hallucis morphology and plantar fascia thickness were measured utilizing diagnostic ultrasound. Plantar foot sensation was assessed at the head of the first metatarsal and medial longitudinal arch using Semmes-Weinstein Monofilaments. Intrinsic foot muscle performance was assessed using the intrinsic foot muscle test (IFMT). Mann-Whitney U and independent t-tests were used to examine between group differences. RESULTS: Individuals with PHP exhibited a more pronated foot posture and greater plantar fascia thickness at the proximal insertion compared to healthy controls. Plantar sensation thresholds were higher in the PHP compared to healthy controls at the head of the first metatarsal. There were no group differences in abductor hallucis morphology or IFMT performance. CONCLUSIONS: Individuals with PHP exhibited a more pronated foot posture, thicker plantar fascia, and diminished plantar tactile sensation.


Assuntos
Artralgia/diagnóstico , Músculo Esquelético/fisiopatologia , Medição da Dor/métodos , Postura/fisiologia , Adulto , Artralgia/fisiopatologia , Estudos Transversais , Feminino , Calcanhar , Humanos , Masculino , Músculo Esquelético/diagnóstico por imagem , Ultrassonografia
2.
Water Res ; 103: 311-318, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27475120

RESUMO

Oil pollution in water and separation of oil from water are receiving much attention in recent years due to the growing environmental concerns. Membrane technology is one of the emerging solutions for oil-water separation. However, there is a limitation in using polymeric membrane for oil water separation due to its surface properties (wetting behaviour), thermal and mechanical properties. Here, we have shown a simple method to increase the hydrophilicity of the polyethersulfone (PES) hollow fibre ultrafiltration (UF) membrane by using carboxyl, hydroxyl and amine modified graphene attached poly acrylonitrile-co-maleimide (G-PANCMI). The prepared membranes were characterized for its morphology, water and oil contact angle, liquid entry pressure of oil (LEPoil), water permeability and finally subjected to a continuous 8 h filtration test of oil emulsion in water. The experimental data indicates that the G-PANCMI play an important role in enhancing the hydrophilicity, permeability and selectivity of the PES membrane. The water contact angle (CAw) of the PES membrane is reduced from 63.7 ± 3.8° to 22.6 ± 2.5° which is 64.5% reduction while, the oil contact angle was increased from 43.6 ± 3.5° to 112.5 ± 3.2° which is 158% higher compared to that of the PES membrane. Similarly, the LEPoil increased 350% from 50 ± 10 kPa of the control PES membrane to 175 ± 25 kPa of PES-G-PANCMI membrane. More importantly, the water permeability increased by 43% with >99% selectivity. Based on our findings we believe that the development of PES-G-PANCMI membrane will open up a solution for successful oil-water separation.


Assuntos
Grafite , Ultrafiltração , Membranas Artificiais , Polímeros , Propriedades de Superfície , Purificação da Água
3.
Sci Rep ; 4: 6949, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25377488

RESUMO

The innovative design and synthesis of nanofiber based hydro-philic/phobic membranes with a thin hydro-phobic nanofiber layer on the top and a thin hydrophilic nanofiber layer on the bottom of the conventional casted micro-porous layer which opens up a solution for membrane pore wetting and improves the pure water flux in membrane distillation.

4.
Sci Rep ; 4: 6555, 2014 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-25296745

RESUMO

Bio-fouling is a serious problem in many membrane-based separation processes for water and wastewater treatment. Current state of the art methods to overcome this are to modify the membranes with either hydrophilic additives or with an antibacterial compound. In this study, we propose and practise a novel concept to prevent bio-fouling by developing a killing and self-cleaning membrane surface incorporating antibacterial silver nanoparticles and highly hydrophilic negatively charged carboxylic and amine functional groups. The innovative surface chemistry helps to reduce the contact angle of the novel membrane by at least a 48% and increase the pure water flux by 39.4% compared to the control membrane. The flux drop for the novel membrane is also lower (16.3% of the initial flux) than the control membrane (55.3% of the initial flux) during the long term experiments with protein solution. Moreover, the novel membrane continues to exhibit inhibition to microbes even after 1320 min of protein filtration. Synthesis of self-cleaning ultrafiltration membrane with long lasting properties opens up a viable solution for bio-fouling in ultrafiltration application for wastewater purification.


Assuntos
Incrustação Biológica , Membranas Artificiais , Águas Residuárias/microbiologia , Purificação da Água , Bactérias/química , Bactérias/isolamento & purificação , Humanos , Metais/química , Compostos Orgânicos/química , Ultrafiltração , Águas Residuárias/química , Água/química
5.
Mol Psychiatry ; 18(4): 461-70, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22430674

RESUMO

Recently, several genome-wide association studies (GWASs) have led to the discovery of nine new loci of genetic susceptibility in Alzheimer's disease (AD). However, the landscape of the AD genetic susceptibility is far away to be complete and in addition to single-SNP (single-nucleotide polymorphism) analyses as performed in conventional GWAS, complementary strategies need to be applied to overcome limitations inherent to this type of approaches. We performed a genome-wide haplotype association (GWHA) study in the EADI1 study (n=2025 AD cases and 5328 controls) by applying a sliding-windows approach. After exclusion of loci already known to be involved in AD (APOE, BIN1 and CR1), 91 regions with suggestive haplotype effects were identified. In a second step, we attempted to replicate the best suggestive haplotype associations in the GERAD1 consortium (2820 AD cases and 6356 controls) and observed that 9 of them showed nominal association. In a third step, we tested relevant haplotype associations in a combined analysis of five additional case-control studies (5093 AD cases and 4061 controls). We consistently replicated the association of a haplotype within FRMD4A on Chr.10p13 in all the data set analyzed (OR: 1.68; 95% CI: (1.43-1.96); P=1.1 × 10(-10)). We finally searched for association between SNPs within the FRMD4A locus and Aß plasma concentrations in three independent non-demented populations (n=2579). We reported that polymorphisms were associated with plasma Aß42/Aß40 ratio (best signal, P=5.4 × 10(-7)). In conclusion, combining both GWHA study and a conservative three-stage replication approach, we characterised FRMD4A as a new genetic risk factor of AD.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Doença de Alzheimer/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Haplótipos/genética , Doença de Alzheimer/sangue , Peptídeos beta-Amiloides/sangue , Estudos de Casos e Controles , Humanos , Polimorfismo de Nucleotídeo Único/genética
6.
Atherosclerosis ; 187(2): 408-14, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16243340

RESUMO

Elevated levels of tumor necrosis factor-alpha (TNF-alpha), and presence of polymorphisms of the TNFA gene have been implicated in cardiovascular disease pathogenesis. We explored the relationship between polymorphisms in the TNFA gene (-1031C/T, -863C/A -857T/C, -308G/A, -238G/A), protein levels of TNF-alpha and their association to myocardial infarction (MI) using a sample of 1213 post-MI patients and 1561 healthy controls. MI risk was higher among men with elevated TNF-alpha levels, with the highest compared to the lowest TNF-alpha quartile giving a 70% risk increase (OR [95% CI]: 1.7 [1.1; 2.6]). Obese subjects who also had elevated TNF-alpha levels were at even higher risk for MI (OR [95% CI]: 3.4 [2.1; 5.6]). Higher TNF-alpha levels were seen among smokers (but not among non-smokers) carrying the -857T allele. Furthermore, a rare haplotype occurred more frequently among the cases than the controls. Elevated TNF-alpha levels are associated with increased MI risk. Obese subjects with elevated TNF-a levels, and carriers of polymorphisms in or near TNFA are particularly susceptible to the hazards of smoking, results which may have implications for cardiovascular preventive measures.


Assuntos
Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/genética , Polimorfismo de Nucleotídeo Único , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/genética , Idoso , Feminino , Predisposição Genética para Doença/epidemiologia , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Obesidade/sangue , Obesidade/epidemiologia , Obesidade/genética , Regiões Promotoras Genéticas/genética , Fatores de Risco , Distribuição por Sexo , Fumar/epidemiologia
7.
Neurology ; 62(11): 2116-8, 2004 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-15184629

RESUMO

The epsilon4 allele of APOE is a risk factor for Alzheimer disease (AD). By analysis of a large cohort of AD patients (n = 563) and control subjects (n = 118), it is shown that the epsilon4 allele is strongly associated with reduced CSF levels of beta-amyloid (1-42) (Abeta42) in both AD (p < 10(-9)) and control (p = 0.0012) populations. As no associations of APOE variants with other indexes of AD severity were observed, this effect may reflect a fundamental involvement of ApoE in Abeta metabolism.


Assuntos
Doença de Alzheimer/genética , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Apolipoproteínas E/genética , Fragmentos de Peptídeos/líquido cefalorraquidiano , Idoso , Idoso de 80 Anos ou mais , Alelos , Doença de Alzheimer/líquido cefalorraquidiano , Apolipoproteína E4 , Estudos de Coortes , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Masculino
8.
J Neural Transm (Vienna) ; 111(2): 191-9, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14767722

RESUMO

Genetic factors play an important role in the aetiology of Parkinson's disease (PD). We have screened nuclear genes encoding subunits of mitochondrial complex I for associations between single nucleotide polymorphisms (SNPs) and PD. Abnormal functioning of complex I is well documented in human PD. Moreover, toxicological inhibition of complex I can lead to parkinsonism in animals. Thus, commonly occurring variants in these genes could potentially influence complex I function and the risk of developing PD. A sub-set of 70 potential SNPs in 31 nuclear complex I genes were selected and association analysis was performed on 306 PD patients plus 321 unaffected control subjects. Genotyping was performed using the DASH method. There was no evidence that the examined SNPs were significant genetic risk factors for PD, although this initial screen could not exclude the possibility that other disease-influencing variations exist within these genes.


Assuntos
DNA Mitocondrial/genética , Complexo I de Transporte de Elétrons/genética , Doença de Parkinson/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Núcleo Celular/genética , Distribuição de Qui-Quadrado , Intervalos de Confiança , Feminino , Frequência do Gene/genética , Humanos , Hibridização Genética/genética , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Polimorfismo de Nucleotídeo Único/genética
9.
Neurosci Lett ; 340(1): 69-73, 2003 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-12648761

RESUMO

Recent studies show linkage between Alzheimer's disease (AD) and two loci on chromosome 10. The cell division cycle 2 (cdc2) gene is located close to one of the chromosome 10 markers, and is a candidate gene for AD since it is involved in the pathogenesis of AD. We sequenced coding exons and flanking intronic sequences and the promoter region on the cdc2 gene and found three new single nucleotide polymorphisms (SNPs). We analyzed 272 Caucasian AD cases, 160 controls and 70 cases with frontotemporal dementia (FTD) for these SNPs. Homozygosity for one of the SNPs (Ex6+7I/D) was more frequent in both AD and FTD cases than in controls. In the combined tauopathy (AD and FTD) group the odds ratio (OR) was 1.77 (95% CI 1.19-2.63) for the Ex6+7II genotype. Our findings suggest that the Ex6+7I allele is associated with tauopathies, both AD and FTD.


Assuntos
Doença de Alzheimer/genética , Proteína Quinase CDC2/genética , Demência/genética , Frequência do Gene/genética , Polimorfismo Genético/genética , Idoso , Idoso de 80 Anos ou mais , Apolipoproteínas E/genética , Divisão Celular/genética , Feminino , Predisposição Genética para Doença/genética , Humanos , Masculino , Pessoa de Meia-Idade
10.
Eur J Hum Genet ; 9(6): 437-44, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11436125

RESUMO

There is considerable enthusiasm for the prospect of using common polymorphisms (primarily single nucleotide polymorphisms; SNPs) in candidate genes to unravel the genetics of complex disease. This approach has generated a number of findings of loci which are significantly associated with sporadic Alzheimer's disease (AD). In the present study, a total of 15 genes of interest were chosen from among the previously published reports of significant association in AD. Genotyping was performed on polymorphisms within those genes (14 SNPs and one deletion) using Dynamic Allele Specific Hybridization (DASH) in 204 Swedish patients with sporadic late-onset AD and 186 Swedish control subjects. The genes chosen for analysis were; low-density lipoprotein receptor-related protein (LRP1), angiotensin converting enzyme (DCP1), alpha-2-macroglobulin (A2M), bleomycin hydrolase (BLMH), dihydrolipoyl S-succinyltransferase (DLST), tumour necrosis factor receptor superfamily member 6 (TNFRSF6), nitric oxide synthase (NOS3), presenilin 1 (PSEN1), presenilin 2 (PSEN2), butyrylcholinesterase (BCHE), Fe65 (APBB1), oestrogen receptor alpha (ESR1), cathepsin D (CTSD), methylenetetrahydrofolate reductase (MTHFR), and interleukin 1A (IL1A). We found no strong evidence of association for any of these loci with AD in this population. While the possibility exists that the genes analysed are involved in AD (ie they have weak effects and/or are population specific), results reinforce the need for extensive replication studies if we are to be successful in defining true risk factors in complex diseases.


Assuntos
Doença de Alzheimer/genética , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único/genética , Alelos , Sequência de Bases , Feminino , Deleção de Genes , Genótipo , Humanos , Masculino , Modelos Estatísticos , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fatores de Risco , Suécia
11.
Trends Genet ; 17(7): 407-13, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11418222

RESUMO

Genetic linkage and association analyses are two distinct approaches to understanding the genetic etiology of complex disease. Association analysis has become particularly popular in recent times, but the true utility of the strategy remains uncertain. To try to gain better insight into the relevant issues, we have used genetic association analysis to explore the etiology of Alzheimer's disease. Our empirical findings supplement the theoretical debate, illustrating the general doubtfulness of previous positive findings and the limited ability of typical association studies based on candidate genes to discern true medium-sized signals from false positives. Improvements in genotyping technologies and increasing the number of SNPs tested, without sophisticated allowance for all other issues, could simply lead to an unmanageable overload of false-positive signals, themselves obscuring true disease associations.


Assuntos
Doença de Alzheimer/genética , Mapeamento Cromossômico/métodos , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Ligação Genética/genética , Humanos , Projetos de Pesquisa , Tamanho da Amostra
12.
Genome Res ; 11(1): 152-62, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11156624

RESUMO

We recently introduced a generic single nucleotide polymorphism (SNP) genotyping method, termed DASH (dynamic allele-specific hybridization), which entails dynamic tracking of probe (oligonucleotide) to target (PCR product) hybridization as reaction temperature is steadily increased. The reliability of DASH and optimal design rules have not been previously reported. We have now evaluated crudely designed DASH assays (sequences unmodified from genomic DNA) for 89 randomly selected and confirmed SNPs. Accurate genotype assignment was achieved for 89% of these worst-case-scenario assays. Failures were determined to be caused by secondary structures in the target molecule, which could be reliably predicted from thermodynamic theory. Improved design rules were thereby established, and these were tested by redesigning six of the failed DASH assays. This involved reengineering PCR primers to eliminate amplified target sequence secondary structures. This sophisticated design strategy led to complete functional recovery of all six assays, implying that SNPs in most if not all sequence contexts can be effectively scored by DASH. Subsequent empirical support for this inference has been evidenced by approximately 30 failure-free DASH assay designs implemented across a range of ongoing genotyping programs. Structured follow-on studies employed standardized assay conditions, and revealed that assay reproducibility (733 duplicated genotypes, six different assays) was as high as 100%, with an assay accuracy (1200 genotypes, three different assays) that exceeded 99.9%. No post-PCR assay failures were encountered. These findings, along with intrinsic low cost and high flexibility, validate DASH as an effective procedure for SNP genotyping.


Assuntos
Alelos , Hibridização de Ácido Nucleico/métodos , Polimorfismo de Nucleotídeo Único/genética , DNA/química , DNA/genética , Primers do DNA/síntese química , Triagem de Portadores Genéticos/métodos , Genótipo , Guias como Assunto , Homozigoto , Humanos , Conformação de Ácido Nucleico , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/normas , Polimorfismo de Fragmento de Restrição , Reprodutibilidade dos Testes , Projetos de Pesquisa/normas , Sensibilidade e Especificidade
13.
Expert Rev Mol Diagn ; 1(3): 352-8, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11901841

RESUMO

Analysis of single nucleotide polymorphisms (SNPs)--the most common form of variation in the human genome--has become a popular strategy for discovering genes involved in complex diseases such as Alzheimer's disease, obesity and diabetes. It is also widely anticipated that SNPs will play a major role in pharmacogenomics, where the identification of variations in specific genes relevant to drug efficacy, toxicity and metabolism will help to establish optimal therapeutic strategies for individual patients. Reflecting these expectations, many new SNP-related technologies have appeared over the past few years, each with unique advantages, but all with the common goal of simplifying and expediting SNP analysis. We recently introduced a technique termed dynamic allele-specific hybridization (DASH), a convenient method for SNP (and insertion-deletion) genotyping, which is highly applicable to both basic research and clinical diagnostics. Commercial DASH devices are now available, making the technology affordably accessible for all laboratories.


Assuntos
Técnicas de Diagnóstico Molecular , Hibridização de Ácido Nucleico , Polimorfismo de Nucleotídeo Único , Alelos , Sequência de Bases , Humanos , Dados de Sequência Molecular , Temperatura
14.
Hum Genet ; 107(4): 391-6, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11129341

RESUMO

The TNFRSF6 gene encodes FAS, a cell-surface receptor involved in apoptosis initiation. Elevated levels of FAS have been reported in the brains of Alzheimer's disease (AD) patients. We have tested a G/A polymorphism at position -670 in the TNFRSF6 gene for association with non-familial, early onset Alzheimer's disease (EOAD) by using dynamic allele-specific hybridization. In an initial set of Scottish EOAD cases (n=78) and controls (n=152), we found that, for individuals carrying one or two APOE4 alleles, the homozygous GG-genotype was enriched in the patients (26.7% versus 10.9% in controls). A second study was conducted on an independent set of Scottish individuals (87 EOAD, 358 controls). In this material, the TNFRSF6 GG-genotype frequency was elevated in patients regardless of APOE4 status (28.7% versus 15.1%) and was even more enriched in APOE4 carriers (35.9% versus 15.3%). A combination of the two sample sets (165 cases, 510 controls) gave a significant disease association for the TNFRSF6 GG-genotype that was irrespective of APOE4 (P=0.0020) and that was almost completely attributable to the enrichment present within the set of APOE4 carriers (P=0.0016). This represents an odds ratio of 8.71 for GG-homozygotes carrying at least one APOE4 allele compared with other TNFRSF6 genotypes in APOE4 non-carriers. The TNFRSF6 variation was further explored in Scottish late-onset Alzheimer's disease (n=159) but no associations were found. These results imply that TNFRSF6, in interaction with APOE4, is a genetic risk factor for sporadic EOAD. Hence, the AD risk contributed by APOE4 could be mechanistically related to a pathway in common with FAS-mediated apoptosis.


Assuntos
Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Receptor fas/genética , Receptor fas/metabolismo , Adulto , Idade de Início , Idoso , Doença de Alzheimer/etiologia , Apoptose , Sequência de Bases , Primers do DNA/genética , Humanos , Pessoa de Meia-Idade , Modelos Biológicos , Polimorfismo Genético , Fatores de Risco
15.
J Neural Transm (Vienna) ; 107(8-9): 1065-79, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11041282

RESUMO

A polymorphism consisting of a deletion near the 5' splice site of exon 18 on the alpha2-macroglobulin (A2M) gene (A2M-2) has been suggested to be associated with Alzheimer's disease (AD) in family-based studies. We studied the A2M-2 allele together with the ApoE alleles in a large series on patients with AD (n = 449) and age-matched controls (n = 349). Neuropathologically confirmed diagnoses were available in 199 cases (94 AD and 107 control cases). We found no increase in A2M-2 genotype or allele frequencies in AD (27.5% and 14.6%) versus controls (26.4% and 14.9%). In contrast, a marked increase (p < 0.0001) in ApoE epsilon4 genotype or allele frequencies was found in AD (66.6% and 41.2%) as compared with controls (29.8% and 16.5%), suggesting sufficient statistical power in our sample. No relation was found between the A2M-2 and the ApoE epsilon4 allele. No change in A2M exon 17-18 mRNA size or sequence or A2M protein size was found in cases carrying the A2M-2 deletion, suggesting that there is no biological consequences of the A2M intronic deletion. No change in A2M protein level in cerebrospinal fluid was found in AD, suggesting that the A2M-2 allele does not effect the A2M protein expression in the brain. The lack of an association between the A2M-2 allele and AD in the present study, and the lack of abnormalities in the A2M mRNA or protein suggest that the A2M-2 allele is not associated with AD.


Assuntos
Doença de Alzheimer/genética , Deleção de Genes , alfa-Macroglobulinas/genética , Idoso , Doença de Alzheimer/patologia , Apolipoproteína E4 , Apolipoproteínas E/genética , Sequência de Bases , Western Blotting , Eletroforese em Gel de Poliacrilamida , Feminino , Expressão Gênica , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Dados de Sequência Molecular , Placa Amiloide/patologia , Polimorfismo Genético , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , População Branca/genética , alfa-Macroglobulinas/análise , alfa-Macroglobulinas/líquido cefalorraquidiano
16.
Neuropsychopharmacology ; 22(3): 284-92, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10693156

RESUMO

In a recent study, we demonstrated that cytochrome-c oxidase (COX), an indicator of neuronal activity, is increased in several brain regions from chronic, medicated schizophrenics. In the present study, to address the functional significance of those findings, we have measured COX activity in a group of schizophrenics in whom antemortem geriatric measures of motor, intellectual, and emotional impairment had been assessed. COX activity in the putamen was strongly negatively correlated with emotional (r = -.76; p < .005) and intellectual impairment (r = -0.76; p < .005), but not with motor impairment (r = 0.01). No significant correlations could be found in the frontal cortex, thalamus, caudate nucleus, globus pallidus, mesencephalon, or nucleus accumbens. Dopamine D2 receptor density in the putamen, measured with [3H]raclopride, was elevated in schizophrenics as compared to controls, as were Kd values. In contrast to COX activity, D2 receptor binding was moderately, but significantly positively correlated with intellectual impairment (r = 0.64; p < .05) but not with motor impairment. Results expose a unique anomaly in the effects of neuroleptics in terms of increasing neuronal signaling in the putamen, which may underlie a reversal of cognitive deficits in schizophrenics, while at the same time, elevating D2 receptor density that seems to be detrimental.


Assuntos
Emoções , Metabolismo Energético , Inteligência , Mitocôndrias/metabolismo , Putamen/metabolismo , Esquizofrenia/metabolismo , Psicologia do Esquizofrênico , Idoso , Idoso de 80 Anos ou mais , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Racloprida/farmacocinética , Receptores de Dopamina D2/metabolismo , Valores de Referência , Análise de Regressão
17.
Gene ; 238(2): 315-24, 1999 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10570959

RESUMO

Catalogs of intra-gene polymorphisms are needed to facilitate wide-ranging candidate gene-based association studies in common complex diseases. With this in mind, we have scanned multiple alignments of expressed sequence tags and of genomic DNA sequences (PCR products from four to eight unrelated individuals) to find polymorphisms in 195 genes putatively involved in neurodegenerative illness (including components of oxidative stress, excitotoxicity, inflammation, apoptosis and aging). This led to the discovery of 167 polymorphisms in 88 genes. These comprised 163 single nucleotide polymorphisms, one insertion/deletion, and three other variations involving more than one base pair. The polymorphisms were distributed in the exons (87), introns (70), and gene flanking regions (10). Of the exonic polymorphisms, 17 would give rise to non-synonymous amino acid substitutions. These findings now provide a valuable resource for association studies in neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease.


Assuntos
Doenças Neurodegenerativas/genética , Polimorfismo de Nucleotídeo Único , Evolução Molecular , Humanos , Reação em Cadeia da Polimerase
18.
Neuropsychopharmacology ; 21(3): 372-9, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10457534

RESUMO

In the present study, we have applied a novel strategy involving the postmortem measurement of the mitochondrial respiratory chain enzyme cytochrome-c oxidase (COX; complex IV) to identify regional changes in energy metabolism in the basal ganglia of chronic, medicated schizophrenics. COX activity was decreased in the caudate nucleus but increased in the putamen and nucleus accumbens. An increase in succinate dehydrogenase (complex II) was evident in the putamen and nucleus accumbens, but changes were not seen with NADH dehydrogenase (complex I). An analysis of interregional correlations in energy metabolism revealed several anomalies in the connections between the caudate and putamen and the globus pallidus in schizophrenics. Results provide strong evidence that changes in baseline energy metabolism in specific regions of the basal ganglia may exist in the disease. Based upon the high degree of input it receives from associative cortical areas, results suggest that a defect in the caudate may underlie certain aspects of cognitive decline in schizophrenics. In contrast, an increase in COX in the putamen, which receives extensive projections from the sensorimotor cortex, may reflect an effect of chronic neuroleptic treatment on motor function.


Assuntos
Gânglios da Base/enzimologia , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Metabolismo Energético/fisiologia , Mitocôndrias/enzimologia , Esquizofrenia/enzimologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Núcleo Caudado/enzimologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , NADH Desidrogenase/metabolismo , Núcleo Accumbens/enzimologia , Putamen/enzimologia , Esquizofrenia/fisiopatologia , Succinato Desidrogenase/metabolismo
19.
J Neural Transm Suppl ; 52: 93-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9564612

RESUMO

Aggregation cultures of rat brain were exposed to a combination of anoxia and hypoglycaemia for 30 minutes. Thereafter, the release of lactate dehydrogenase into the cell culture medium was monitored up to 4 days as a measure of cell damage after the ischemic insult. Some cultures were treated with different concentrations of deprenyl or tolcapone, selective inhibitors of monoamine oxidase B and catechol-O-methyltransferase, respectively. After 1 day in culture, the release of lactate dehydrogenase was significantly reduced in cultures treated with deprenyl (at 1 nM. 100 nM, and 10 microM), as well as in cultures treated with 1 nM or 100 nM tolcapone; 10 microM of tolcapone, on the other hand, resulted in a toxic effect on the cell aggregates. No differences in the release of lactate dehydrogenase into the medium was observed in the aggregates treated with drugs as compared with the control cultures after 2 or 4 days post-ischemia.


Assuntos
Benzofenonas/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Inibidores da Monoaminoxidase/farmacologia , Neurônios/citologia , Fármacos Neuroprotetores/farmacologia , Prosencéfalo/citologia , Selegilina/farmacologia , Animais , Isquemia Encefálica , Inibidores de Catecol O-Metiltransferase , Células Cultivadas , Embrião de Mamíferos , L-Lactato Desidrogenase , Modelos Neurológicos , Neurônios/efeitos dos fármacos , Nitrofenóis , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Tolcapona
20.
Eur Neuropsychopharmacol ; 8(1): 1-6, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9452933

RESUMO

Regional alterations in neuronal functional activity were examined in the rat brain using cytochrome-c oxidase (COX) histochemistry following chronic neuroleptic treatment. Haloperidol, fluphenazine, and clozapine were administered to animals for 28 days after which profiles of COX activity were generated. Significant increases in COX activity were evident in area 2 of the frontal cortex of all treated animals. Clozapine and fluphenazine, but not haloperidol, caused significant increases in COX activity in the caudate nucleus, nucleus accumbens, septum, and pontine nucleus. Statistically significant increases in COX activity were also observed in hippocampal CA2 and CA3 subfields in clozapine treated animals. Results offer support for the concept that neuroleptics achieve their therapeutic effects primarily via an enhancement of brain function in the frontal cortex, but also point to other brain regions which may be involved in the actions of these drugs.


Assuntos
Antipsicóticos/farmacologia , Encéfalo/enzimologia , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Animais , Encéfalo/anatomia & histologia , Encéfalo/efeitos dos fármacos , Clozapina/farmacologia , Densitometria , Flufenazina/farmacologia , Haloperidol/farmacologia , Histocitoquímica , Masculino , Ratos , Ratos Sprague-Dawley
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