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511.
ABSTRACT: BACKGROUND: Psychiatric comorbidity is common in back pain patients undergoing disc surgery and increases economic costs in many areas of health. The objective of this study was to analyse psychiatric comorbidity as predictor of direct and indirect costs in back pain patients undergoing disc surgery in a longitudinal study design. METHODS: A sample of 531 back pain patients was interviewed after an initial disc surgery (T0), 3 months (T1) and 15 months (T2) using the Composite International Diagnostic Interview to assess psychiatric comorbidity and a modified version of the Client Sociodemographic and Service Receipt Inventory to assess resource utilization and lost productivity for a 3-month period prior interview. Health care utilization was monetarily valued by unit costs and productivity by labour costs. Costs were analysed using random coefficient models and bootstrap techniques. RESULTS: Psychiatric comorbidity was associated with significantly (p<0.05) increased direct (+664 Euro) and indirect costs (+808 Euro) at T0. The direct cost difference predominantly resulted from medical health care utilization and was nearly unchanged at T2. Further important cost predictors were clinical variables like the presence of chronic medical disease, the number of previous disc surgeries, and time and gender. CONCLUSION: Psychiatric comorbidity presents an important predictor of direct and indirect costs in back pain patients undergoing disc surgery, even if patients do not utilize mental health care. This effect seems to be stable over time. More attention should be given to psychiatric comorbidity and cost-effective treatments should be applied to treat psychiatric comorbidity in back pain patients undergoing disc surgery to reduce comorbidity induced health care utilization and costs.  相似文献   
512.

Purpose:

To apply myelin‐sensitive quantitative magnetic resonance imaging (MRI) techniques in defined hypomyelinating conditions and to identify spatial patterns of myelination as criteria for characterization of undefined disorders.

Materials and Methods:

Seven patients were included, based on the diagnosis of mitochondrial cytopathy, Pelizaeus‐Merzbacher disease, GJA12/GJC2‐related Pelizaeus‐Merzbacher‐like disease, hypomyelination with atrophy of the basal ganglia and cerebellum, and leukoencephalopathy with ataxia, delayed dentition, and hypomyelination. The control group comprised 23 children and adolescents (age range 2.6–22.4 years). The 3T MRI protocol consisted of high‐resolution T1‐ and T2‐weighted 3D MRI, diffusion tensor (DTI), and magnetization transfer (MT) imaging. Parameter maps of mean diffusivity, fractional anisotropy, and MT saturation were displayed as pseudocolor overlays and assessed by region‐of‐interest and histogram analysis.

Results:

Structural MRI revealed widespread signal alterations in white matter, but were hampered by signal heterogeneity. Quantitative DTI and MT reflected the degree of hypomyelination and discriminative patterns of myelination emerged on MT saturation maps.

Conclusion:

The quantitative parameters in the defined hypomyelination conditions provide additional criteria to further classify undefined white matter disorders. J. Magn. Reson. Imaging 2012; 36:1329–1338. © 2012 Wiley Periodicals, Inc.  相似文献   
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Infantile-onset spinocerebellar ataxia (IOSCA) is a severe neurodegenerative disorder caused by the recessive mutation in PEO1, leading to an Y508C change in the mitochondrial helicase Twinkle, in its helicase domain. However, no mitochondrial dysfunction has been found in this disease. We studied here the consequences of IOSCA for the central nervous system, as well as the in vitro performance of the IOSCA mutant protein. The results of the mtDNA analyses were compared to findings in a similar juvenile or adult-onset ataxia syndrome, mitochondrial recessive ataxia syndrome (MIRAS), caused by the W748S mutation in the mitochondrial DNA polymerase (POLG). We show here that IOSCA brain does not harbor mtDNA deletions or increased amount of mtDNA point mutations, whereas MIRAS brain shows multiple deletions of mtDNA. However, IOSCA, and to a lesser extent also MIRAS, show mtDNA depletion in the brain and the liver. In both diseases, especially large neurons show respiratory chain complex I (CI) deficiency, but also CIV is decreased in IOSCA. Helicase activity, hexamerization and nucleoid structure of the IOSCA mutant were, however, unaffected. The lack of in vitro helicase defect or cell culture phenotype suggest that Twinkle-Y508C dysfunction affects mtDNA maintenance in a highly context and cell-type specific manner. Our results indicate that IOSCA is a new member of the mitochondrial DNA depletion syndromes.  相似文献   
515.
Moth pheromones cause rises in intracellular Ca(2+) concentrations that activate Ca(2+)-dependent cation channels in antennal olfactory receptor neurons. In addition, mechanisms of adaptation and sensitization depend on changes in cyclic nucleotide concentrations. Here, cyclic nucleotide-activated currents in cultured olfactory receptor neurons of the moth Manduca sexta are described, which share properties with currents through vertebrate cyclic nucleotide-gated channels. The cyclic nucleotide-activated currents of M. sexta carried Ca(2+) and monovalent cations. They were directly activated by cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP), modulated by Ca(2+)/calmodulin, and inhibited by lanthanum. M. sexta cyclic nucleotide-activated currents developed in an all-or-none manner, which suggests that the underlying channels are coupled and act coordinately. At least one cAMP- and two cGMP-activated nonselective cation currents could be distinguished. Compared with the cAMP-activated current, both cGMP-activated currents appeared to conduct more Ca(2+) and showed a stronger down-regulation by Ca(2+)/calmodulin-dependent negative feedback. Furthermore, both cGMP-activated currents differed in their Ca(2+)-dependent inhibition. Thus M. sexta olfactory receptor neurons, like vertebrate sensory neurons, appear to express nonselective cyclic nucleotide-activated cation channels with different subunit compositions. Besides the nonselective cyclic nucleotide-activated cation currents, olfactory receptor neurons express a cAMP-dependent current. This current resembled a protein kinase-modulated low-voltage-activated Ca(2+) current.  相似文献   
516.
An accurate diagnosis is essential for the management of late‐life depression in primary care. This study aims to (1) provide information on the agreement on depression diagnoses between general practitioners (GPs), dimensional tools (Geriatric Depression Scale [GDS], Hospital Anxiety and Depression Scale [HADS]) and a categorical tool (Structured Clinical Interview for DSM‐IV criteria [SCID]) and (2) identify factors associated with different diagnoses. As part of the multicenter study “Late‐life depression in primary care: needs, health care utilization and costs (AgeMooDe)” a sample of 1113 primary care patients aged 75 years and older was assessed. The proportion of depression was 24.3% according to GPs, 21.8% for the GDS, 18.9% for the HADS and 8.2% for the SCID. Taking GDS, HADS and SCID as reference standards, recognition of GPs was 47%, 48% and 63%. Cohen's Kappa values indicate slight to moderate agreement between diagnoses. Multinomial logistic regression models showed that patient related factors of depression were anxiety, intake of antidepressants, female gender, a low state of health, intake of medication for chronic diseases and functional impairment. GPs performed better at ruling out depression than ruling in depression. High levels of disagreement between different perspectives on depression indicate that they may be sensitive to different aspects of depression.  相似文献   
517.
S-Vinyl monomers react readily in radical polymerizations resulting in polymers with interesting features such as enhanced refractive indices, increased thermal stability, or the ability to coordinate various metals. Among them, vinyl mercaptoethanol (VME) can be produced in industrial scale, but the poor solubility of the resulting homopolymer limits its application. In this contribution, polymerizations of the monomer are investigated in water forming a heterogeneous system. The good solubility of the monomer in water imparts the system with mixed characteristics between a precipitation and an emulsion polymerization. Evaluating various surfactants, only polyvinyl alcohol (PVA) is found to create stable dispersions, although micrometer-sized particles are formed with a broad size distribution. Nevertheless, the particles are able to coordinate silver or gold ions. Attempts to reduce the noble metal ions by commercial reducing agents fail. However, exposure to sunlight unexpectedly results in a controlled reduction of the metal ions and the formation of composite particles. Silver ion-containing dispersions demonstrate strong antibacterial properties, while the effect is diminished in the corresponding composite. Overall, the precipitation/emulsion polymerization of VME represents a promising pathway to stable sulfur-rich polymer dispersions with the ability to coordinate metal ions or form reactive metal composites.  相似文献   
518.
International Journal of Clinical Oncology - To explore correlations between the clinical attributes of secondary bladder cancer and brachytherapy, we retrospectively reviewed our institutional...  相似文献   
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