A cross-sectional study of inpatients with late stage of dementia in Southeast China and the associations between biochemical parameters and apolipoprotein E genotypes.

BACKGROUND: The purpose of this study was to analyze the disease distribution of patients in the late stage of dementia through a cross-sectional investigation and to clarify the association between apolipoprotein E (APOE) genotypes and the serum levels of total cholesterol, total triglycerides, and blood glucose in the late-stage Alzheimer's disease (AD) patients. METHODS: Patients who were in the late stage of dementia in a mental health center were enrolled in this study. A broad battery of neuropsychological tests and neuroimaging was applied to make the diagnosis. The APOE genotype was determined by the multiplex amplification refractory mutation system polymerase chain reaction. The association between APOE genotype and the blood level of biochemical parameters was studied. RESULTS: A total of 155 patients were enrolled in this study. The majority of patients had AD (67.8%), followed by vascular dementia (15.5%), mixed dementia (9%), and others (7.7%). The APOE ε4 allele frequency was significantly different in the different groups. The serum level of total cholesterol (TC) in APOE ε4 carriers was higher than in non-carriers (P<0.05). No statistically significant differences were found in the blood glucose and triglycerides (TG) levels between these two groups. CONCLUSION: To our knowledge, this is the first paper to study the characteristics of late-stage dementia in hospital patients in Southeast China. We found that the disease distribution was quite consistent with previous prevalence studies. Moreover, we found that the serum level of TC was higher in APOE ε4 carriers group. However, no association was found between the APOE ε4 allele and serum levels of glucose, TC and TG in the late stage of AD.

[Seven-Point Correction Approach for Spectrum Measurement of Light Source with a Narrow Bandwidth].

The finite bandwidth of spectroradiometers always causes significant errors when the measured light source has a narrow bandwidth compared to that of spectroradiometers. In order to solve this problem, an improved correction approach which is called seven-point correction approach is proposed. Firstly, the seven-point correction formula is obtained with Taylor's series and related derivative formula. Secondly, the effect of seven-point formula is validated through a simulated spectrum with a sine function shape. Considering the sine function as true spectrum, we calculate the measured spectrum with the bandpass function of spectroradiometers. We also correct the measured spectrum with the seven-point formula. At last, we validate the seven-point formula experimentally with a LED lamp whose center wavelength is 365 nm. Using a double grating monochromator, we measure the irradiance of LED lamp when the bandwidth of spectroradiometer is 5 and 0.5 nm. We also obtain the corrected spectrum by applying seven-point formula to measured spectrum. The simulated results show that, the corrected value at the center wavelength could be above 99% of the true value. The experimental results show that, the corrected value at the center wavelength could reach above 95% of the true value. Above all, the proposed seven-point approach has an improved correction effect compared with three-point and five point approach. This correction approach could be widely applied in the field of spectrum measurement.

Fabrication of fluorescent magnetic Fe3O4@ZnS nanocomposites.

A novel Fe3O4@ZnS nanomaterial with fluorescent and superparamagnetic properties has been successfully fabricated via TOPO-TOP synthesis with an additional coordinating component (OAm). The adsorption of OAm on the preformed magnetite nanoparticles, which were prepared in phenyl ether with oleic acid and oleyl amine, played an essential role in directing the structure of the Fe3O4@ZnS composites. The obtained materials were characterized by FTIR, TEM, XRD, X-ray photoelectron spectroscopy (XPS), UV-vis, fluorescence spectrophotometer and VSM. The results indicated that the Fe3O4 nanoparticles were successfully combined with ZnS and the coating of ZnS can be controlled by adjusting the molar ratio of Fe3O4 to ZnS. The saturation magnetization values of Fe3O4, Fe3O4@ZnS (1:2) and Fe3O4@ZnS (1:5) nanoparticles are 57.0 emu g(-1), 44.4 emu g(-1) and 34.2 emu g(-1), respectively at 300 K and the nanocomposites exhibit better fluorescence without evident quenching. The combined magnetic and fluorescent properties endow the nanocomposites with great potential applications in "nano-conveyer-belt" platform technology for drug targeting, bioseparation, diagnostic analysis and so on.