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Using 125I-labeled rabbit anti-Hodgkin's spleen ferritin antibody (RHF), a simple radioimmunoassay has been developed for quantitation of ferritin on the surface of peripheral blood mononuclear white blood cells (PBM). This method makes use of a % specific binding determination (%SP) by measuring the amount of 125I-labeled RHF bound to 1 × 106 PBM in the presence and absence of soluble ferritin. To standardize this procedure, artificial ferritin positive control cells were prepared by covalently coupling ferritin to cultured acute lymphoblastic luekemia cells. These cells were tested on a daily basis in parallel with patient PBM's to ensure inter and intra-assay precision and remained stable for over two years. Characteristics of 125I-labeled RHF binding to control and patient PBM's were evaluated to determine the specificity of interaction and optimum binding parameters. %SP was linear in the range of 1 × 105 - 1 × 106 PBM's and was progressively inhibited by graded concentrations of soluble ferritin. F(ab')2 preparations of RHF were equally as effective as intact RHF in blocking 125I-labeled RHF binding confirming that 125I-labeled RHF was not binding non-specifically to PBM Fc receptors. Additional experiments describing kinetics and methods of standardization of new lots of 125I-labeled RHF are also described.  相似文献   
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Background

When facing the well-known demographic development with an increasing number of people suffering from dementia, there is a need of programmes to support nursing relatives and care at home. Many support services have been established in the past few years but they are rarely used by the relatives and the patients. The purpose of the Lighthouse Project Ulm (ULTDEM Study) was to prove the effectiveness of a single advisory approach in order to provide support services after care level classification and to relieve the burden placed on relatives caring for family members suffering from dementia (“initial case management”).

Methods

The ULTDEM Study is a prospective, open, randomized, controlled, interventional study with different parallel outcome measures (burden of caring, quality of life and mood). After the randomization, the interventional group was given comprehensive, individual advice about available treatment possibilities for dementia patients. Control group participants received standard treatment. Inclusion criteria were application of a care level (0 or 1) as well as dementia diagnosis. All participants (patients/relatives) underwent an initial and a 6?month comprehensive assessment.

Results

Our results show that a single advisory approach does not lead to a significant difference in outcome measures in interventional and control groups. Those tendencies described have to be interpreted as clinically not relevant. Although utilization of support services increases, it remains similar in both study groups. A confirmatory interpretation has not been possible due to a lack of adjustment to the findings regarding multiple testing and an insufficient degree of recruitment. Possible causes will be discussed such as premature intervention during the course of the disease, a lack of intervention blinding, recruitment bias and lack of an influence on adherence with regard to the use of support services.

Implications

The study demonstrates that there is a substantial information deficit for persons affected by dementia and their relatives. Innovative ways still have to be developed to ensure that this information actually reaches the target audience.  相似文献   
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The source of acellular specimens is not infrequently challenged, especially for toxicology specimens, but such specimens may not be amenable to conventional genetic testing to confirm the source. Our evaluation of genomic and mitochondrial DNA (mtDNA) amplicons using polymerase chain reaction (PCR) from centrifuged, filtered, or whole urine specimens demonstrated higher sensitivity of detection of mtDNA than genomic DNA and a higher detection rate for the mtDNA markers than genomic markers in all sample sets. The mitochondrial amplicons were sequenced to identify specific single nucleotide polymorphisms (SNPs). Subsequently, a real-time PCR technique using fluorescence resonance energy transfer (FRET) probes designed to hybridize to the published mtDNA sequence over known SNP locations present within the mitochondrial control region was developed. Our results demonstrate the feasibility of using a FRET-based assay of mitochondrial genotypes with acellular laboratory specimens to screen for specimen mix-ups or to confirm sources of controversial toxicology specimens.  相似文献   
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