66 resultados para Complex Disease


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Lung function measures are heritable, predict mortality and are relevant in diagnosis of chronic obstructive pulmonary disease (COPD). COPD and asthma are diseases of the airways with major public health impacts and each have a heritable component. Genome-wide association studies of SNPs have revealed novel genetic associations with both diseases but only account for a small proportion of the heritability. Complex copy number variation may account for some of the missing heritability. A well-characterised genomic region of complex copy number variation contains beta-defensin genes (DEFB103, DEFB104 and DEFB4), which have a role in the innate immune response. Previous studies have implicated these and related genes as being associated with asthma or COPD. We hypothesised that copy number variation of these genes may play a role in lung function in the general population and in COPD and asthma risk. We undertook copy number typing of this locus in 1149 adult and 689 children using a paralogue ratio test and investigated association with COPD, asthma and lung function. Replication of findings was assessed in a larger independent sample of COPD cases and smoking controls. We found evidence for an association of beta-defensin copy number with COPD in the adult cohort (OR = 1.4, 95%CI:1.02-1.92, P = 0.039) but this finding, and findings from a previous study, were not replicated in a larger follow-up sample(OR = 0.89, 95%CI:0.72-1.07, P = 0.217). No robust evidence of association with asthma in children was observed. We found no evidence for association between beta-defensin copy number and lung function in the general populations. Our findings suggest that previous reports of association of beta-defensin copy number with COPD should be viewed with caution. Suboptimal measurement of copy number can lead to spurious associations. Further beta-defensin copy number measurement in larger sample sizes of COPD cases and children with asthma are needed.

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Background Visual symptoms are common in Parkinson's disease (PD) and are frequently under-diagnosed. The detection of visual symptoms is important for differential diagnosis and patient management. Aim To establish the prevalence of recurrent visual complaints (RVC) and recurrent visual hallucinations (RVH) and to investigate their interaction in PD patients and controls. Methods This cross-sectional study included 88 PD patients and 90 controls. RVC and RVH were assessed with a visual symptom questionnaire and the North-East-Visual-Hallucinations-Interview (NEVHI). Results Double vision (PD vs. Controls: 18.2% vs. 1.3%; p < 0.001), misjudging objects when walking (PD vs. Controls: 12.5% vs. 1.3%; p < 0.01), words moving whilst reading (PD vs. Controls: 17.0% vs. 1.3%; p < 0.001) and freezing in narrow spaces (PD vs. Controls: 30.7% vs. 0%; p < 0.001) were almost exclusively found in PD patients. The same was true for recurrent complex visual hallucinations and illusions (PD vs. Controls: both 17.0% vs. 0%; p < 0.001). Multiple RVC (43.2% vs. 15.8%) and multiple RVH (29.5% vs. 5.6%) were also more common in PD patients (both p < 0.001). RVC did not predict recurrent complex visual hallucinations; but double vision (p = 0.018, R2 = 0.302) and misjudging objects (p = 0.002, R2 = 0.302) predicted passage hallucinations. Misjudging objects also predicted the feeling of presence (p = 0.010, R2 = 0.321). Conclusions Multiple and recurrent visual symptoms are common in PD. RVC emerged as risk factors predictive of the minor forms of hallucinations, but not recurrent complex visual hallucinations.

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Parkinson's disease, typically thought of as a movement disorder, is increasingly recognized as causing cognitive impairment and dementia. Eye movement abnormalities are also described, including impairment of rapid eye movements (saccades) and the fixations interspersed between them. Such movements are under the influence of cortical and subcortical networks commonly targeted by the neurodegeneration seen in Parkinson's disease and, as such, may provide a marker for cognitive decline. This study examined the error rates and visual exploration strategies of subjects with Parkinson's disease, with and without cognitive impairment, whilst performing a battery of visuo-cognitive tasks. Error rates were significantly higher in those Parkinson's disease groups with either mild cognitive impairment (P = 0.001) or dementia (P < 0.001), than in cognitively normal subjects with Parkinson's disease. When compared with cognitively normal subjects with Parkinson's disease, exploration strategy, as measured by a number of eye tracking variables, was least efficient in the dementia group but was also affected in those subjects with Parkinson's disease with mild cognitive impairment. When compared with control subjects and cognitively normal subjects with Parkinson's disease, saccade amplitudes were significantly reduced in the groups with mild cognitive impairment or dementia. Fixation duration was longer in all Parkinson's disease groups compared with healthy control subjects but was longest for cognitively impaired Parkinson's disease groups. The strongest predictor of average fixation duration was disease severity. Analysing only data from the most complex task, with the highest error rates, both cognitive impairment and disease severity contributed to a predictive model for fixation duration [F(2,76) = 12.52, P ≤ 0.001], but medication dose did not (r = 0.18, n = 78, P = 0.098, not significant). This study highlights the potential use of exploration strategy measures as a marker of cognitive decline in Parkinson's disease and reveals the efficiency by which fixations and saccades are deployed in the build-up to a cognitive response, rather than merely focusing on the outcome itself. The prolongation of fixation duration, present to a small but significant degree even in cognitively normal subjects with Parkinson's disease, suggests a disease-specific impact on the networks directing visual exploration, although the study also highlights the multi-factorial nature of changes in exploration and the significant impact of cognitive decline on efficiency of visual search.

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OBJECTIVE Parkinson disease dementia (PDD) and dementia with Lewy bodies (DLB) have overlapping clinical and pathologic features. Recurrent visual hallucinations (RVH) are common in both disorders. The authors have compared details of hallucination characteristics and associated neuropsychiatric features in DLB and PDD. METHODS This is a descriptive, cross-sectional study using the Institute of Psychiatry Visual Hallucinations Interview (IP-VHI) to explore self-reported frequency, duration, and phenomenology of RVH in PDD and DLB. The caregivers' ratings of hallucinations and other neuropsychiatric features were elicited with the Neuropsychiatric Inventory (NPI). RESULTS Fifty-six patients (35 PDD; 21 DLB) with RVH were assessed. Hallucination characteristics were similar in both disorders. Simple hallucinations were rare. Most patients experienced complex hallucinations daily, normally lasting minutes. They commonly saw people or animals and the experiences were usually perceived as unpleasant. NPI anxiety scores were higher in PDD. Neuropsychiatric symptoms coexisting with hallucinations were apathy, sleep disturbance, and anxiety. CONCLUSIONS Patients with mild to moderate dementia can provide detailed information about their hallucinations. Characteristics of RVH were similar in PDD and DLB, and phenomenology suggests the involvement of dorsal and ventral visual pathways in their generation. The coexistence of RVH with anxiety, apathy, and sleep disturbance is likely to impair patients' quality of life and may have treatment implications.

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Neurodegeneration in Parkinson's disease dementia (PDD) and dementia with Lewy bodies (DLB) affect cortical and subcortical networks involved in saccade generation. We therefore expected impairments in saccade performance in both disorders. In order to improve the pathophysiological understanding and to investigate the usefulness of saccades for differential diagnosis, saccades were tested in age- and education-matched patients with PDD (n = 20) and DLB (n = 20), Alzheimer's disease (n = 22) and Parkinson's disease (n = 24), and controls (n = 24). Reflexive (gap, overlap) and complex saccades (prediction, decision and antisaccade) were tested with electro-oculography. PDD and DLB patients had similar impairment in all tasks (P > 0.05, not significant). Compared with controls, they were impaired in both reflexive saccade execution (gap and overlap latencies, P < 0.0001; gains, P < 0.004) and complex saccade performance (target prediction, P < 0.0001; error decisions, P < 0.003; error antisaccades: P < 0.0001). Patients with Alzheimer's disease were only impaired in complex saccade performance (Alzheimer's disease versus controls, target prediction P < 0.001, error decisions P < 0.0001, error antisaccades P < 0.0001), but not reflexive saccade execution (for all, P > 0.05). Patients with Parkinson's disease had, compared with controls, similar complex saccade performance (for all, P > 0.05) and only minimal impairment in reflexive tasks, i.e. hypometric gain in the gap task (P = 0.04). Impaired saccade execution in reflexive tasks allowed discrimination between DLB versus Alzheimer's disease (sensitivity > or =60%, specificity > or =77%) and between PDD versus Parkinson's disease (sensitivity > or =60%, specificity > or =88%) when +/-1.5 standard deviations was used for group discrimination. We conclude that impairments in reflexive saccades may be helpful for differential diagnosis and are minimal when either cortical (Alzheimer's disease) or nigrostriatal neurodegeneration (Parkinson's disease) exists solely; however, they become prominent with combined cortical and subcortical neurodegeneration in PDD and DLB. The similarities in saccade performance in PDD and DLB underline the overlap between these conditions and underscore differences from Alzheimer's disease and Parkinson's disease.

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Insect bite hypersensitivity (IBH) is an allergic dermatitis of horses caused by bites of insects. IBH is a multifactorial disease with contribution of genetic and environmental factors. Candidate gene association analysis of IBH was performed in a group of 89 Icelandic horses all born in Iceland and imported to Europe. Horses were classified in IBH-affected and non-affected based on clinical signs and history of recurrent dermatitis, and on the results of an in vitro sulfidoleukotriene (sLT)-release assay with Culicoides nubeculosus and Simulium vittatum extract. Different genetic markers were tested for association with IBH by the Fisher's exact test. The effect of the major histocompatibility complex (MHC) gene region was studied by genotyping five microsatellites spanning the MHC region (COR112, COR113, COR114, UM011 and UMN-JH34-2), and exon 2 polymorphisms of the class II Eqca-DRA gene. Associations with Eqca-DRA and COR113 were identified (p < 0.05). In addition, a panel of 20 single nucleotide polymorphisms (SNPs) in 17 candidate allergy-related genes was tested. During the initial screen, no marker from the panel was significantly (p < 0.05) associated with IBH. Five SNPs associated with IBH at p < 0.10 were therefore used for analysis of combined genotypes. Out of them, SNPs located in the genes coding for the CD14 receptor (CD14), interleukin 23 receptor (IL23R), thymic stromal lymphopoietin (TSLP) and transforming growth factor beta 3 (TGFB3) molecules were associated with IBH as parts of complex genotypes. These results are supported by similar associations and by expression data from different horse populations and from human studies.

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The macronuclear genome of the ciliate Oxytricha trifallax displays an extreme and unique eukaryotic genome architecture with extensive genomic variation. During sexual genome development, the expressed, somatic macronuclear genome is whittled down to the genic portion of a small fraction (∼5%) of its precursor "silent" germline micronuclear genome by a process of "unscrambling" and fragmentation. The tiny macronuclear "nanochromosomes" typically encode single, protein-coding genes (a small portion, 10%, encode 2-8 genes), have minimal noncoding regions, and are differentially amplified to an average of ∼2,000 copies. We report the high-quality genome assembly of ∼16,000 complete nanochromosomes (∼50 Mb haploid genome size) that vary from 469 bp to 66 kb long (mean ∼3.2 kb) and encode ∼18,500 genes. Alternative DNA fragmentation processes ∼10% of the nanochromosomes into multiple isoforms that usually encode complete genes. Nucleotide diversity in the macronucleus is very high (SNP heterozygosity is ∼4.0%), suggesting that Oxytricha trifallax may have one of the largest known effective population sizes of eukaryotes. Comparison to other ciliates with nonscrambled genomes and long macronuclear chromosomes (on the order of 100 kb) suggests several candidate proteins that could be involved in genome rearrangement, including domesticated MULE and IS1595-like DDE transposases. The assembly of the highly fragmented Oxytricha macronuclear genome is the first completed genome with such an unusual architecture. This genome sequence provides tantalizing glimpses into novel molecular biology and evolution. For example, Oxytricha maintains tens of millions of telomeres per cell and has also evolved an intriguing expansion of telomere end-binding proteins. In conjunction with the micronuclear genome in progress, the O. trifallax macronuclear genome will provide an invaluable resource for investigating programmed genome rearrangements, complementing studies of rearrangements arising during evolution and disease.

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Background Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disorder in industrialized countries, yet its pathophysiology is incompletely understood. Small-molecule metabolite screens may offer new insights into disease mechanisms and reveal new treatment targets. Methods Discovery (N = 33) and replication (N = 66) of liver biopsies spanning the range from normal liver histology to non-alcoholic steatohepatitis (NASH) were ascertained ensuring rapid freezing under 30 s in patients. 252 metabolites were assessed using GC/MS. Replicated metabolites were evaluated in a murine high-fat diet model of NAFLD. Results In a two-stage metabolic screening, hydroquinone (HQ, pcombined = 3.0 × 10−4) and nicotinic acid (NA, pcombined = 3.9 × 10−9) were inversely correlated with histological NAFLD severity. A murine high-fat diet model of NAFLD demonstrated a protective effect of these two substances against NAFLD: Supplementation with 1% HQ reduced only liver steatosis, whereas 0.6% NA reduced both liver fat content and serum transaminase levels and induced a complex regulatory network of genes linked to NALFD pathogenesis in a global expression pathway analysis. Human nutritional intake of NA equivalent was also consistent with a protective effect of NA against NASH progression. Conclusion This first small-molecular screen of human liver tissue identified two replicated protective metabolites. Either the use of NA or targeting its regulatory pathways might be explored to treat or prevent human NAFLD.

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A complex interaction among metabolic factors, adipose tissue lipolysis, oxidative stress, and insulin resistance results in a deleterious process that may link nonalcoholic fatty liver disease (NAFLD) with severe cardiovascular (CV) outcomes. Patients with NAFLD are at higher risk of atherosclerosis, new onset of CV events, and overall mortality. The strong association between NAFLD and CV disease should affect clinical practice, with screening and surveillance of patients with NAFLD. This review discusses the data linking these major diseases.

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OBJECTIVE To analyse the results after elective open total aortic arch replacement. METHODS We analysed 39 patients (median age 63 years, median logistic EuroSCORE 18.4) who underwent elective open total arch replacement between 2005 and 2012. RESULTS In-hospital mortality was 5.1% (n = 2) and perioperative neurological injury was 12.8% (n = 5). The indication for surgery was degenerative aneurysmal disease in 59% (n = 23) and late aneurysmal formation following previous surgery of type A aortic dissection in 35.9% (n = 14); 5.1% (n = 2) were due to anastomotical aneurysms after prior ascending repair. Fifty-nine percent (n = 23) of the patients had already undergone previous proximal thoracic aortic surgery. In 30.8% (n = 12) of them, a conventional elephant trunk was added to total arch replacement, in 28.2% (n = 11), root replacement was additionally performed. Median hypothermic circulatory arrest time was 42 min (21-54 min). Selective antegrade cerebral perfusion was used in 95% (n = 37) of patients. Median follow-up was 11 months [interquartile range (IQR) 1-20 months]. There was no late death and no need for reoperation during this period. CONCLUSIONS Open total aortic arch replacement shows very satisfying results. The number of patients undergoing total arch replacement as a redo procedure and as a part of a complex multisegmental aortic pathology is high. Future strategies will have to emphasize neurological protection in extensive simultaneous replacement of the aortic arch and adjacent segments.

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Much of the research on visual hallucinations (VHs) has been conducted in the context of eye disease and neurodegenerative conditions, but little is known about these phenomena in psychiatric and nonclinical populations. The purpose of this article is to bring together current knowledge regarding VHs in the psychosis phenotype and contrast this data with the literature drawn from neurodegenerative disorders and eye disease. The evidence challenges the traditional views that VHs are atypical or uncommon in psychosis. The weighted mean for VHs is 27% in schizophrenia, 15% in affective psychosis, and 7.3% in the general community. VHs are linked to a more severe psychopathological profile and less favorable outcome in psychosis and neurodegenerative conditions. VHs typically co-occur with auditory hallucinations, suggesting a common etiological cause. VHs in psychosis are also remarkably complex, negative in content, and are interpreted to have personal relevance. The cognitive mechanisms of VHs in psychosis have rarely been investigated, but existing studies point to source-monitoring deficits and distortions in top-down mechanisms, although evidence for visual processing deficits, which feature strongly in the organic literature, is lacking. Brain imaging studies point to the activation of visual cortex during hallucinations on a background of structural and connectivity changes within wider brain networks. The relationship between VHs in psychosis, eye disease, and neurodegeneration remains unclear, although the pattern of similarities and differences described in this review suggests that comparative studies may have potentially important clinical and theoretical implications.

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(Full text is available at http://www.manu.edu.mk/prilozi). New generation genomic platforms enable us to decipher the complex genetic basis of complex diseases and Balkan Endemic Nephropathy (BEN) at a high-throughput basis. They give valuable information about predisposing Single Nucleotide Polymorphisms (SNPs), Copy Number Variations (CNVs) or Loss of Heterozygosity (LOH) (using SNP-array) and about disease-causing mutations along the whole sequence of candidate-genes (using Next Generation Sequencing). This information could be used for screening of individuals in risk families and moving the main medicine stream to the prevention. They also might have an impact on more effective treatment. Here we discuss these genomic platforms and report some applications of SNP-array technology in a case with familial nephrotic syndrome. Key words: complex diseases, genome wide association studies, SNP, genomic arrays, next generation sequ-encing.

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Recently, many studies about a network active during rest and deactivated during tasks emerged in the literature: the default mode network (DMN). Spatial and temporal DMN features are important markers for psychiatric diseases. Another prominent indicator of cognitive functioning, yielding information about the mental condition in health and disease, is working memory (WM) processing. In EEG studies, frontal-midline theta power has been shown to increase with load during WM retention in healthy subjects. From these findings, the conclusion can be drawn that an increase in resting state DMN activity may go along with an increase in theta power in high-load WM conditions. We followed this hypothesis in a study on 17 healthy subjects performing a visual Sternberg WM task. The DMN was obtained by a BOLD-ICA approach and its dynamics represented by the percent-strength during pre-stimulus periods. DMN dynamics were temporally correlated with EEG theta spectral power from retention intervals. This so-called covariance mapping yielded the spatial distribution of the theta EEG fluctuations associated with the dynamics of the DMN. In line with previous findings, theta power was increased at frontal-midline electrodes in high- versus low-load conditions during early WM retention. However, load-dependent correlations of DMN with theta power resulted in primarily positive correlations in low-load conditions, while during high-load conditions negative correlations of DMN activity and theta power were observed at frontal-midline electrodes. This DMN-dependent load effect reached significance during later retention. Our results show a complex and load-dependent interaction of pre-stimulus DMN activity and theta power during retention, varying over the course of the retention period. Since both, WM performance and DMN activity, are markers of mental health, our results could be important for further investigations of psychiatric populations.

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Members of the Mycobacterium tuberculosis complex (MTBC) cause a serious disease with similar pathology, tuberculosis; in this review, bovine tuberculosis will be considered as disease caused by any member of the MTBC in bovids. Bovine tuberculosis is responsible for significant economic loss due to costly eradication programs and trade limitations and poses a threat to both endangered and protected species as well as to public health. We here give an overview on all members of the MTBC, focusing on their isolation from different animal hosts. We also review the recent advances made in elucidating the evolutionary and phylogenetic relationships of members of the MTBC. Because the nomenclature of the MTBC is controversial, its members have been considered species, subspecies or ecotypes, this review discusses the possible implications for diagnostics and the legal consequences of naming of new species.

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OBJECTIVE Visual hallucinations (VHs) are a very personal experience, and it is not clear whether information about them is best provided by informants or patients. Some patients may not share their hallucinatory experiences with caregivers to avoid distress or for fear of being labeled insane, and others do not have informants at all, which limits the use of informant-based questionnaires. The aim of this study was to compare patient and caregiver views about VHs in Parkinson disease (PD), using the North-East Visual Hallucinations Interview (NEVHI). METHODS Fifty-nine PD patient-informant pairs were included. PD patients and informants were interviewed separately about VHs using the NEVHI. Informants were additionally interviewed using the four-item version of the Neuropsychiatric Inventory. Inter-reliability and concurrent validity of the different measures were compared. RESULTS VHs were more commonly reported by patients than informants. The inter-rater agreement between NEVHI-patient and NEVHI-informant was moderate for complex VHs (Cohen's kappa = 0.44; 95% confidence interval [CI]: 0.13-0.75; t = 3.43, df = 58, p = 0.001) and feeling of presence (Cohen's kappa = 0.35; 95% CI: 0.00-0.70; t = 2.75, df = 58, p = 0.006), but agreement was poor for illusions (Cohen's kappa = 0.25; 95% CI: -0.07-0.57; t = 2.36, df = 58, p = 0.018) and passage hallucinations (Cohen's kappa = 0.16; 95% CI: -0.04-0.36; t = 2.26, df = 58, p = 0.024). CONCLUSION When assessing VHs in PD patients, it is best to rely on patient information, because not all patients share the details of their hallucinations with their caregivers.