Biomedical subjects

Yan Li

Publications and source records attributed to Yan Li.

At least 253 records · Page 14Linked to original sources

PubMed2006

[Comparative analysis via data mining on the clinical features of Western medicine and Chinese medicine in diagnosing rheumatoid arthritis].

OBJECTIVE: To compare the clinical characteristics of traditional Chinese medicine (TCM) and Western medicine (WM) in diagnosing rheumatoid arthritis (RA). METHODS: A total of 85 clinical RA related messages were enacted and classified into 5 sets as pathological locations, quantitative diagnosis, symptomatic descriptions, general status and environment factors. The respective frequency of their presence in the TCM or WM data sets for RA diagnosis collected from MEDLINE and China National Knowledge Infrastructure (CNKI) were analyzed statistically by Chi-square test, and the relationship of some TCM diagnostic factors/conditions with the RA related biological factors was analyzed by co-occurrence-based literature approach of mining. RESULTS: There was significant difference between the diagnostic pattern of WM and TCM (P < 0.01). Compared with that of WM, TCM diagnosis on RA paid more attention to environmental factors and symptomatic descriptions, which showed definite association with the cytokines and neuro-endocrine factors in RA. CONCLUSION: Examination of environmental factors and symptomatic descriptions for RA diagnosis is one of the important characteristics of TCM treatment in accordance to syndrome differentiation, it has its potential biologic basis. A novel approach is proposed for exploring the characteristics of TCM in diagnosis and observation.

Arthritis, Rheumatoid↗

PubMed2006

[Role of bone marrow-derived mesenchymal stem cells in reduction of graft-versus-host disease by effecting CD4+CD25+ regulatory T cells in rats].

The study was purposed to investigate the effects and mechanism of bone marrow-derived mesenchymal stem cells (MSCs) on graft-versus-host desease (GVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). The model of GVHD in rat had been established by allo-HSCT with donor derived T cells. The occurence of GVHD in recipients was observed in condition with or without donor derived MSC co-transplantation. Effects of MSCs on GVHD were analyzed by model rat survival rate and pathology. Proportions of CD4+CD25+ regulatory T cells were determined by using label spleen lymphocytes and thymocytes with double fluorescent-labeled antibodies and flow cytometry. The results showed that MSCs inhibited the lethal GVHD after HSC co-transplantation and increased the survival rate. The ratio of CD4/CD8 deceased in GVHD group in different levels, as compared with that in the experimental group. The proportion of CD4+CD25+ regulatory T cells of spleen lymphocytes was 31.55 +/- 7.58% and 20.90 +/- 1.90% in experimental and GVHD groups, respectively. Similarly, the proportion of CD4+CD25+ regulatory T cells of thymocytes was 93.20 +/- 2.69% and 57.17 +/- 6.79% in experimental and the GVHD groups, respectively. Meanwhile the proportion of CD4+CD25+ regulatory T cells was higher in experimental group than that in GVHD group. It is concluded that MSCs may prevent the lethal GVHD after allo-HSC co-transplantation and raise the survival rate of model rats by acting on the CD4+CD25+ regulatory T cells in vivo.

Animals↗

PubMed2006

[A review on applications of infrared spectroscopy to the study of traditional Chinese medicine].

Infrared spectroscopy is well suited for the rapid and nondestructive identification and quantification of traditional Chinese medicine (TCM) for its high resolution, easy operation and strong specialization of absorbance bands. It is becoming an efficient methodology in the quality control of TCM. The present paper reviews the applications of infrared spectrometry in the qualitative and quantitative analysis of TCM, especially to the discrimination and effective content determination of traditional Chinese medicinal materials (including different parts of the same medicinal material, TCM from different geographical areas, easily confusing TCM, and true and false TCM) and Chinese patent medicine (such as TCM formula particles, injections, etc.). With the ceaseless rapid development and popularization of FTIR spectrometer and computer science, infrared spectrometry will greatly accelerate the process of TCM modernization and internationalization by all means.

Medicine, Chinese Traditional↗

PubMed2006

[Advanced development of remote sensing FTIR in air environment monitoring].

Remote sensing FTIR(RS-FTIR) is one of the most important technologies in atmospheric pollutant monitoring. It has several prevailing advantages: (1) high resolution and high selectivity; (2) it requiring no sampling and no sample preprocessing; (3) capability of detecting several compounds simultaneously; (4) real time, long distance, and automatic monitoring. So it is extraordinarily appropriate for the quantitative and qualitative determination, and remote, real time, dynamic monitoring of air contaminant, especially the toxic volatile organic compounds (VOCs). The present paper reviews the research progress in remote sensing FTIR for air monitoring made by the Laboratory of Advanced Spectroscopy in recent years, including chemometrics, computed tomography, FTIR spectra interpretation, spatial distribution of air pollutant concentration and passive remote monitoring, etc. These research findings show that the rapid development and application of remote sensing FTIR accelerated the temporal and spatial extension of analytical chemistry, and it will by all means have wide prospects in atmospheric environmental monitoring.

English Abstract↗

PubMed2005

[5C + 1S] annulation: a facile and efficient synthetic route toward functionalized 2,3-dihydrothiopyran-4-ones.

[reaction: see text] A facile and efficient synthetic route toward highly substituted 2,3-dihydrothiopyran-4-ones 2 has been developed via a formal [5C + 1S] annulation of readily available alpha-alkenoyl ketene-(S,S)-acetals 1 with sodium sulfide nonahydrated salt (Na2S x 9H2O) and utilized in the synthesis of 2-(4-chlorophenyl)-6-(morpholin-4-yl)-4H-thiopyran-4-one 5l, an inhibitor of DNA-dependent protein kinase (DNA-PK).

Journal Article↗

PubMed2005

[Protective effects of bicyclol on alcohol-induced liver damage in mice].

OBJECTIVE: To study the protective effect of bicyclol on alcohol-induced liver injury in mice. METHODS: Sixty male mice were randomly divided into 6 groups. Ten mice were fed with Lieber-Decarli liquid diet without alcohol and used as normal controls. Fifty mice were fed with Lieber-Decarli liquid diet containing 5% alcohol for four weeks so as to establish a model of alcohol-induced liver damage. Ten mice fed with Lieber-Decarli liquid diet containing 5% alcohol for four weeks were used as model group. Bicyclol in a dose of either 200 or 300 .kg(-1).d(-1) was given orally simultaneously with alcohol intake as prevention groups (10 mice in each group), and bicyclol in a dose of either 200 or 300 .kg(-1).d(-1) was given orally 2 weeks after the beginning of alcohol intake as treatment groups (10 mice in each group). Twenty-four hours after the last dose of bicyclol the mice were decapitated and then their blood samples and livers were taken. The serum alanine aminotransferase (ALT), cholesterol (CHOL), and high-density lipoprotein/low-density lipoprotein (HDL/LDL), and liver triglyceride (TG), N-nitrosodimethylamine demethylase (NDMA-DM), glutathione (GSH), glutathione S-transferase (GST), glutathione reductase (GR), and aldehyde dehydrogenase (ALDH) were determined by biochemical assays. The extent of liver damage was evaluated by histological examination. RESULTS: Four weeks after alcohol intake the serum ALT and TG were 1.9 and 2.7 times those of the normal control group. The levels of liver TG of the bicyclol 200 kg(-1).d(-1) and 300 kg(-1).d(-1) treatment groups were significantly lower than that of the model group by 28% and 32% respectively (both P < 0.05). The levels of liver TG of the bicyclol 200 kg(-1).d(-1) and 300 kg(-1).d(-1) prevention groups were significantly lower than that of the model group by 32%, and 47% respectively (both P < 0.01). Pathological changes including steatosis and hepatocyte ballooning degeneration were found in the livers of the model group. The levels of liver GSH, GST, and GR in the model group decreased by 37%, 22%, and 19% in comparison with the normal control group. The levels of liver GSH and GST of the bicyclol prevention groups were normal, and the liver GR level was 1.2 times that of the normal control group. The liver NDMA-DM activity of the model group was 1.9 times that of the normal control group and was normal in the bicyclol prevention and treatment groups. The liver cytoplasmic ALDH level was 30% lower in the model group than in the normal control group (P < 0.05), and was 2.9 times in the bicyclol groups (P < 0.01). The serum cholesterol levels of the bicyclol groups were all significantly lower than that of the model group (all P < 0.01). The serum levels of HDL of the bicyclol prevention groups and treatment were all significantly lower than that in the model group (P < 0.01 or P < 0.05). CONCLUSION: Bicyclol protects mice against alcohol-induced hepatotoxicity by reduction of hepatic steatosis and cellular damage, acceleration of alcohol and aldehyde elimination and anti-peroxidation.

Alanine Transaminase↗

PubMed2005

Different domains control the localization and mobility of LIKE HETEROCHROMATIN PROTEIN1 in Arabidopsis nuclei.

Plants possess a single gene for the structurally related HETEROCHROMATIN PROTEIN1 (HP1), termed LIKE-HP1 (LHP1). We investigated the subnuclear localization, binding properties, and dynamics of LHP1 proteins in Arabidopsis thaliana cells. Transient expression assays showed that tomato (Solanum lycopersicum) LHP1 fused to green fluorescent protein (GFP; Sl LHP1-GFP) and Arabidopsis LHP1 (At LHP1-GFP) localized to heterochromatic chromocenters and showed punctuated distribution within the nucleus; tomato but not Arabidopsis LHP1 was also localized within the nucleolus. Mutations of aromatic cage residues that recognize methyl K9 of histone H3 abolished their punctuated distribution and localization to chromocenters. Sl LHP1-GFP plants displayed cell type-dependent subnuclear localization. The diverse localization pattern of tomato LHP1 did not require the chromo shadow domain (CSD), whereas the chromodomain alone was insufficient for localization to chromocenters; a nucleolar localization signal was identified within the hinge region. Fluorescence recovery after photobleaching showed that Sl LHP1 is a highly mobile protein whose localization and retention are controlled by distinct domains; retention at the nucleolus and chromocenters is conferred by the CSD. Our results imply that LHP1 recruitment to chromatin is mediated, at least in part, through interaction with methyl K9 and that LHP1 controls different nuclear processes via transient binding to its nuclear sites.

Amino Acid Sequence↗

PubMed2005

Biodegradable hyaluronic acid/n-carboxyethyl chitosan/protein ternary complexes as implantable carriers for controlled protein release.

An ampholytic N-carboxyethyl chitosan (CEC), with various isoelectric points (IPs), was synthesized by grafting acrylic acid on chitosan utilizing Michael's reaction. Compared to native chitosan, CEC has enhanced water solubility and dramatically accelerated enzymatic degradation; the rate of degradation is proportional to the degree of substitution (DS). The results from turbidimetric titration and fluorescence studies revealed that CEC formed complexes with either hyaluronic acid (HA) or bovine serum albumin (BSA) within a certain pH range. The HA/CEC/BSA ternary complexes could be prepared by colloid titration with quantitative yield and BSA entrapment. The rate of BSA release from the complexes was affected by pH, ionic strength, DS of CEC, and the molecular weight (MW) of HA. The endurance of BSA release from the complexes could be extended up to 20 d by formulating them with high-MW HA and CEC with low DS.BSA release profiles from HA/CEC-2/BSA complexes.

Absorbable Implants↗

PubMed2005

Enhancement of excitatory synaptic transmission in spiny neurons after transient forebrain ischemia.

Spiny neurons in the neostriatum are highly vulnerable to ischemia. Enhancement of excitatory synaptic transmissions has been implicated in ischemia-induced excitotoxic neuronal death. Here we report that evoked excitatory postsynaptic currents in spiny neurons were potentiated after transient forebrain ischemia. The ischemia-induced potentiation in synaptic efficacy was associated with an enhancement of presynaptic release as demonstrated by an increase in the frequency of miniature excitatory postsynaptic currents (mEPSCs) and a decrease in the paired-pulse ratio. The amplitude of inward currents evoked by exogenous application of glutamate did not show significant changes after ischemia, suggesting that postsynaptic mechanism is not involved. The ischemia-induced increase in mEPSCs frequency was not affected by blockade of voltage-gated calcium channels, but it was eliminated in the absence of extracellular calcium. Bath application of ATP P2X receptor antagonist pyridoxal-phosphate-6-azophenyl-2',4'-disulfonic acid (PPADS) significantly reduced mEPSC frequency in ischemic neurons but had no effects on the control ones. Furthermore, the inhibitory effect of PPADS on ischemic neurons was abolished in Ca2+-free external solution. These results indicate that excitatory synaptic transmissions in spiny neurons are potentiated after ischemia via presynaptic mechanisms. Activation of P2X receptors and the consequent Ca2+ influx might contribute to the ischemia-induced facilitation of glutamate release.

Action Potentials↗

PubMed2005

Characterization of two new variants of human catechol O-methyltransferase in vitro.

Catechol O-methyltransferase (COMT) plays an important role in the inactivation of biologically active and toxic catechols. It has been shown that human soluble COMT (S-COMT) is genetically polymorphic with a wild type and at least one variant in which a valine has been substituted with a methionine at codon 108. This polymorphism has been the subject of intense molecular epidemiological studies because of the important role of COMT in the metabolism of catecholamines and catechol estrogens. Several epidemiological studies have shown that women, homozygous with the Val108Met variant, have an increased risk of developing estrogen-associated cancers. However, some other studies have shown that this COMT polymorphism is not associated with increased risk of developing cancers. These conflicting data suggest that additional COMT genetic variants might contribute to the increased risk of developing cancers. Although two new single nucleotide polymorphisms (SNP) that cause amino acid substitutions Ala22Ser and Ala52Thr have been identified recently, they have not been fully characterized. In the present study, Ala22Ser and Ala52Thr variants of human S-COMT were produced using recombinant DNA techniques, and then COMT properties were measured including enzymatic activity, thermostability, and sensitivity to inhibition mediated by 4-hydroxyequilenin (4-OHEN). The Ala22Ser variant showed lower methylation capacity and higher thermolability. In addition, this variant is sensitive to 4-OHEN mediated irreversible inhibition. Our data indicate that the Ala22Ser polymorphism might also be of functional significance and might play a role in susceptibility to estrogen-associated cancers.

Alanine↗

PubMed2005

Ion-nanotube terahertz oscillator.

We report the intriguing dynamics of a potassium ion interacting with a 16 A carbon nanotube. The ion induces a strong dielectric response in the nanotube wall that can be described through a self-consistent tight-binding method. The polarization of the nanotube was found to play a critical role in the ion-nanotube interaction, which exhibits a low access barrier of only 1.05 kcal/mol and a deep, attractive well with a depth of about 30 kcal/mol. An ion bound in the nanotube is predicted to oscillate at a frequency of about 0.4 terahertz, dragging the electrons of the nanotube along. Besides its appealing nature in low-dimensional physics, such a nano-oscillator may serve as a room temperature terahertz wave detector.

Algorithms↗

PubMed2005

Creation of cadmium sulfide nanostructures using AFM dip-pen nanolithography.

A dip-pen nanolithography (DPN) process capable of depositing nanoscaled structures of semiconducting CdS materials was developed by careful control of the reaction speed between the precursors. The new development expanded the scope of the powerful DPN process and provided more insight in the deposition mechanism. Features ranging from several hundreds of nanometers to sub-50 nanometers were generated and characterized. The effects of the surface property of the substrate, the relative humidity, the translating rate, and the temperature were systematically investigated. X-ray photoelectron spectroscopy (XPS) was used to verify the chemical composition of the patterns. In principle, this simple and convenient method should be applicable to deposit various metal sulfides on suitable substrates.

Journal Article↗

PubMed2005

Polymorphisms in tumor necrosis factor genes and susceptibility to esophageal squamous cell carcinoma and gastric cardiac adenocarcinoma in a population of high incidence region of North China.

BACKGROUND: We investigated the possible association of the functional polymorphisms in the tumor necrosis factor (TNF) genes with susceptibility to esophageal squamous cell carcinoma (ESCC) and gastric cardiac adenocarcinoma (GCA). METHODS: The TNF-alpha-308G/A and TNF-beta+252G/A single nucleotide polymorphisms (SNPs) were genotyped using polymerase-chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis, in 555 cancer patients (291 ESCC and 264 GCA) and 437 healthy controls in a high incidence region of North China. RESULTS: Among healthy controls, frequencies of the TNF-alpha 1/1, 1/2 and 2/2 genotypes were 89.4%, 9.2% and 1.4% respectively, while frequencies of the TNF-beta B1/B1, B1/B2 and B2/B2 genotypes were 12.6%, 32.3% and 55.1%, respectively. No significant difference was found in the overall genotype and allelotype distribution of the TNF-alpha-308G/A and TNF-beta+252G/A SNPs among cancer patients and controls. However, both the B1/B1 genotype and B1/B2 genotype significantly increased the risk of developing ESCC [the age and gender adjusted odds ratio (OR) = 2.04 and 1.91, 95% confidence interval (CI) = 1.04 - 4.43 and 1.14 - 2.60, respectively] and GCA (the age and gender adjusted OR = 2.68 and 2.64, 95% CI = 1.14 - 6.29 and 1.47 - 4.72, respectively) in individuals with negative family history of UGIC, in comparison with the B2/B2 genotype. When the two TNF polymorphisms were combined and analyzed, individuals with the TNF-beta B1/B2 and TNF-alpha 1/2 or 2/2 genotypes significantly reduced the risk of developing ESCC and GCA, in comparison with those harboring the TNF-beta B2/B2 and TNF-alpha 1/1 genotypes (the age and gender adjusted OR = 0.37 and 0.34, 95% CI = 0.15 - 0.92 and 0.13 - 0.90, respectively). CONCLUSIONS: Therefore, the TNF-alpha-308G/A and TNF-beta+252G/A genotyping may be used as a stratification markers to predicate the risk of ESCC and GCA development in North China.

Adenocarcinoma↗

PubMed2005

Identification and quantitative determination of benproperine metabolites in human plasma and urine by liquid chromatography-tandem mass spectrometry.

Two novel metabolites of benproperine (BPP), 1-[1-methyl-2-[2-(phenylmethyl)phenoxy]ethyl]-3-piperidinol (3-OH-BPP) and 1-[1-methyl-2-[2-(phenylmethyl)phenoxy]ethyl]-4-piperidinol (4-OH-BPP), were confirmed by comparison of retention times and mass spectra with those of synthetic standards using liquid chromatography-tandem mass spectrometry. Selective and sensitive procedures were developed for the simultaneous determination of BPP, 3-OH-BPP and 4-OH-BPP in human plasma and urine. The analytes were extracted from plasma sample and enzymatically hydrolyzed urine samples by liquid-liquid extraction, separated through a Diamonsil C(18) column (150 mm x 4.6 mm i.d.) and determined by tandem mass spectrometry with an electrospray ionization interface in selected reaction monitoring mode. Dextromethorphan was used as internal standard. The mobile phase consisted of acetonitrile-water-formic acid (34:66:1, v/v/v), and flow-rate was 0.5 ml min(-1). This method has a lower limit of quantification (LLOQ) of 60, 4.0 and 4.0 nmol l(-1)for BPP, 3-OH-BPP and 4-OH-BPP in plasma, 4.9, 4.7 and 2.4 nmol l(-1) in urine, respectively. The intra- and inter-run precision were measured to be below 9.2%, and the accuracy was within +/-4.3% for the analytes. The method was successfully used to determine BPP, 3-OH-BPP and 4-OH-BPP in plasma and urine for pharmacokinetic investigation. The results indicated residue of 3-OH-BPP in the body at least 192 h after an oral dose of BPP.

Antitussive Agents↗

PubMed2005

Polymorphisms in the promoter regions of the matrix metalloproteinases-1, -3, -7, and -9 and the risk of epithelial ovarian cancer in China.

PURPOSE: To investigate the association of single nucleotide polymorphisms (SNP) in the promoter region of the matrix metalloproteinases-1 -1607bp1G/2G, matrix metalloproteinases-3 -1171bp5A/6A, matrix metalloproteinases-7 A-181G and matrix metalloproteinases-9 C-1562T with susceptibility to ovarian cancer in a population of North China. EXPERIMENTAL DESIGN: We analyzed four different functional promoter polymorphisms in the respective genes by polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) in a sample of patients with epithelium ovarian cancer and control women, all from North China. RESULTS: No significant difference was detected between the patient and control groups in genotype and allelotype distribution of MMP-1, MMP-3, MMP-9 of the polymorphisms studied. However, the genotype and allelotype of the MMP-7 distribution in ovarian cancer patients were significantly different from that in healthy controls. The frequency of the -181G allele of MMP-7 in patients was significantly higher than that in healthy controls women (8.2% vs. 2.8%, P = 0.002). Compared to the A/A genotype, the genotypes with the -181G allele (A/G + G/G) significantly increased susceptibility to ovarian cancer, with adjusted odds ratio [OR] = 3.53 95% confidence interval [CI] [1.58 to 7.89]. CONCLUSIONS: The study suggested that a possible association between the MMP-7 A/G polymorphism with susceptibility to epithelium ovarian cancer, but there is no support for an association of the selected MMP-1 1G/2G, MMP-3 5A/6A, and MMP-9 C/T polymorphisms with the risk for ovarian cancer.

Adult↗

PubMed2005

Correlation between CK18 gene and gastric carcinoma micrometastasis.

AIM: To explore the biological behavior of gastric carcinoma micrometastasis (MM) with a marker of cytokeratin 18 (CK18) and to evaluate the clinical stage of gastric carcinoma and its prognosis. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) was used to examine the expression of CK18 mRNA in 298 lymph nodes from 35 patients with gastric carcinoma and 20 lymph nodes from 10 patients with chronic peptic ulcer and gastric perforation diagnosed by pathological examination and surgery. CK18 mRNA expression of peripheral blood from 54 patients with gastric carcinoma and 10 healthy people were also examined. RESULTS: Expression of CK18 mRNA was not found in 10 patients with benign pathological changes. CK18 mRNA expression in gastric carcinoma tissues was strongly positive. In gastric carcinoma patients, pathological examination revealed that 99 of 298 (33.2%) lymph nodes were positive, while RT-PCR showed that 133 of 298 (44.6%) lymph nodes had expression of CK18 mRNA. The difference was significant (P<0.05). Among the 199 negative lymph nodes identified by pathological examinations, 34 (17.1%) displayed positive expression of CK18 mRNA by RT-PCR. The positive expression of CK18 mRNA was associated with lymph node micrometastasis (LMM) of gastric carcinoma. CK18 mRNA was negatively expressed in all 10 healthy cases and positively expressed in 38.9% of 54 blood specimens from gastric carcinoma patients. The positive rate was not correlated with tumor invasion of gastric carcinoma, but was significantly associated with TNM stage, lymph node metastasis (P=0.0290, P<0.05) and tumor differentiation (P=0.2956, P<0.05). CONCLUSION: RT-PCR with CK18 mRNA as a molecular marker is highly sensitive and specific in detecting LMM of gastric carcinoma. It can benefit the diagnosis of MM and guide studies on biological behavior, clinical phase, and therapy as well as relapse monitoring.

Adult↗

PubMed2005

Dominant expression of 85-kDa form of cortactin in colorectal cancer.

PURPOSE: Cortactin is commonly expressed in several human cancers, which may alter their invasive or metastatic properties. Eighty five kilodalton form (p85) and 80-kDa form (p80) of cortactin are two separate bands in SDS-PAGE representing different conformational states. The objective of this study was to investigate cortactin expression in colorectal cancer (CRC). EXPERIMENTAL DESIGN: Cortactin expression was studied in an eight paired laser capture microdissection (LCM) CRC tissues and matched non-cancerous epithelia by immunoblotting. The expression in 58 CRC and two cell lines, HCT8 and HCT116, was studied respectively by immunohistochemistry and confocal laser scanning immunofluorescence. RESULTS: Dominant expression of p85 was identified in LCM-procured CRC tissues compared with equal intensity of p85 and p80 forms in non-cancerous tissues, while the amount of total cortactin was approximate. Immunohistochemistry analysis demonstrated that cortactin located in the cytoplasm of tumor cells and adjacent non-cancerous cells, and its expression was negatively correlated with TNM staging and lymphatic invasion status. However, the invasion fronts in 3 of 58 primary tumors and 28 of 39 available lymph node metastases were intensively stained. Further, immunofluorescence analysis showed that cortactin was distributed in cytoplasm and enriched in the front of the extending lamellipodia at adhering side of cultured cancer cells. CONCLUSIONS: Our results demonstrated the dominant expression of p85 form of cortactin in CRC for the first time. The enrichment of cortactin in the invasion front of some tumor cells and in the extending lamellipodia of cultured cancer cells suggests that cortactin may help cancer cell movement.

Biomarkers, Tumor↗

PubMed2005

Change in cognitive function in Alzheimer's disease in African-American and white persons.

Few studies have examined the association of race with change in cognitive function in Alzheimer's disease (AD). We studied the rate of decline in global and specific measures of cognitive function in a cohort of 410 older African-Americans and whites with clinically diagnosed AD. Persons were examined annually for an average of 3.5 years, and follow-up participation among survivors exceeded 90%. In mixed-effects models that controlled for age, gender, education, and premorbid reading activity, African-Americans scored lower than whites at baseline on a composite measure of global cognition and on specific measures of visuoconstruction and naming. However, they experienced less rapid decline in episodic memory (p < 0.01), with similar but not quite significant effects for global cognition (p = 0.06), perceptual speed (p = 0.07) and naming (p = 0.08). The results suggest that the rate of cognitive decline in AD is slower in African-Americans compared with whites, particularly for episodic memory.

Aged↗