Aberrant Topological Patterns of Structural Covariance Networks in Cognitively Normal Elderly Adults With Mild Behavioral Impairment.

Mild behavioral impairment (MBI), characterized by the late-life onset of sustained and meaningful neuropsychiatric symptoms, is increasingly recognized as a prodromal stage of dementia. However, the underlying neural mechanisms of MBI remain unclear. Here, we examined alterations in the topological organization of the structural covariance networks of patients with MBI (N = 32) compared with normal controls (N = 38). We found that the gray matter structural covariance networks of both the patients with MBI and controls exhibited a small-world topology evidenced by sigma value larger than one. The patients with MBI had significantly decreased clustering coefficients at several network densities and local efficiency at densities ranging from 0.05 to 0.26, indicating decreased local segregation. No significant differences in the characteristic path length, gamma value, sigma value, or global efficiency were detected. Locally, the patients with MBI showed significantly decreased nodal betweenness centrality in the left middle frontal gyrus, right inferior frontal gyrus (opercular part), and left Heschl gyrus and increased betweenness centrality in the left gyrus rectus, right insula, bilateral precuneus, and left thalamus. Moreover, the difference in the bilateral precuneus survived after correcting for multiple comparisons. In addition, a different number and distribution of hubs was identified in patients with MBI, showing more paralimbic hubs than observed in the normal controls. In conclusion, we revealed abnormal topological patterns of the structural covariance networks in patients with MBI and offer new insights into the network dysfunctional mechanisms of MBI.

Distinct Patterns of Brain Atrophy associated with Mild Behavioral Impairment in Cognitively Normal Elderly Adults.

A cross-sectional study was conducted to evaluate patterns of gray matter changes in cognitively normal elderly adults with mild behavioral impairment (MBI). Sixteen MBI patients and 18 healthy controls were selected. All the participants underwent a neuropsychological assessment battery, including the Mini-mental State Examination (MMSE), Geriatric Depression Scale (GDS), Self-rating Anxiety Scale (SAS), and Chinese version of the mild behavioral impairment-checklist scale (MBI-C), and magnetic resonance imaging (MRI) scans. Imaging data was analyzed based on voxel-based morphometry (VBM). There was no significant difference in age, gender, MMSE score, total intracranial volume, white matter hyperdensity, gray matter volume, white matter volume between the two groups (p > 0.05). MBI group had shorter education years and higher MBI-C score, GDS and SAS scores than the normal control group (p < 0.05). For neuroimaging analysis, compared to the normal control group, the MBI group showed decreased volume in the left brainstem, right temporal transverse gyrus, left superior temporal gyrus, left inferior temporal gyrus, left middle temporal gyrus, right occipital pole, right thalamus, left precentral gyrus and left middle frontal gyrus(uncorrected p < 0.001). The grey matter regions correlated with the MBI-C score included the left postcentral gyrus, right exterior cerebellum, and left superior frontal gyrus. This suggests a link between MBI and decreased grey matter volume in cognitively normal elderly adults. Atrophy in the left frontal cortex and right thalamus in MBI patients is in line with frontal-subcortical circuit deficits, which have been linked to neuropsychiatric symptoms (NPS) in dementia. These initial results imply that MBI might be an early harbinger for subsequent cognitive decline and dementia.

A rapid discrimination of authentic and unauthentic Radix Angelicae Sinensis growth regions by electronic nose coupled with multivariate statistical analyses.

Radix Angelicae Sinensis, known as Danggui in China, is an effective and wide applied material in Traditional Chinese Medicine (TCM) and it is used in more than 80 composite formulae. Danggui from Minxian County, Gansu Province is the best in quality. To rapidly and nondestructively discriminate Danggui from the authentic region of origin from that from an unauthentic region, an electronic nose coupled with multivariate statistical analyses was developed. Two different feature extraction methods were used to ensure the authentic region and unauthentic region of Danggui origin could be discriminated. One feature extraction method is to capture the average value of the maximum response of the electronic nose sensors (feature extraction method 1). The other one is to combine the maximum response of the sensors with their inter-ratios (feature extraction method 2). Multivariate statistical analyses, including principal component analysis (PCA), soft independent modeling of class analogy (SIMCA), and hierarchical clustering analysis (HCA) were employed. Nineteen samples were analyzed by PCA, SIMCA and HCA. Then the remaining samples (GZM1, SH) were projected onto the SIMCA model to validate the models. The results indicated that, in the use of feature extraction method 2, Danggui from Yunnan Province and Danggui from Gansu Province could be successfully discriminated using the electronic nose coupled with PCA, SIMCA and HCA, which suggested that the electronic-nose system could be used as a simple and rapid technique for the discrimination of Danggui between authentic and unauthentic region of origin.

Classification of EEG signals using a multiple kernel learning support vector machine.

In this study, a multiple kernel learning support vector machine algorithm is proposed for the identification of EEG signals including mental and cognitive tasks, which is a key component in EEG-based brain computer interface (BCI) systems. The presented BCI approach included three stages: (1) a pre-processing step was performed to improve the general signal quality of the EEG; (2) the features were chosen, including wavelet packet entropy and Granger causality, respectively; (3) a multiple kernel learning support vector machine (MKL-SVM) based on a gradient descent optimization algorithm was investigated to classify EEG signals, in which the kernel was defined as a linear combination of polynomial kernels and radial basis function kernels. Experimental results showed that the proposed method provided better classification performance compared with the SVM based on a single kernel. For mental tasks, the average accuracies for 2-class, 3-class, 4-class, and 5-class classifications were 99.20%, 81.25%, 76.76%, and 75.25% respectively. Comparing stroke patients with healthy controls using the proposed algorithm, we achieved the average classification accuracies of 89.24% and 80.33% for 0-back and 1-back tasks respectively. Our results indicate that the proposed approach is promising for implementing human-computer interaction (HCI), especially for mental task classification and identifying suitable brain impairment candidates.

Identifying patients with poststroke mild cognitive impairment by pattern recognition of working memory load-related ERP.

The early detection of subjects with probable cognitive deficits is crucial for effective appliance of treatment strategies. This paper explored a methodology used to discriminate between evoked related potential signals of stroke patients and their matched control subjects in a visual working memory paradigm. The proposed algorithm, which combined independent component analysis and orthogonal empirical mode decomposition, was applied to extract independent sources. Four types of target stimulus features including P300 peak latency, P300 peak amplitude, root mean square, and theta frequency band power were chosen. Evolutionary multiple kernel support vector machine (EMK-SVM) based on genetic programming was investigated to classify stroke patients and healthy controls. Based on 5-fold cross-validation runs, EMK-SVM provided better classification performance compared with other state-of-the-art algorithms. Comparing stroke patients with healthy controls using the proposed algorithm, we achieved the maximum classification accuracies of 91.76% and 82.23% for 0-back and 1-back tasks, respectively. Overall, the experimental results showed that the proposed method was effective. The approach in this study may eventually lead to a reliable tool for identifying suitable brain impairment candidates and assessing cognitive function.

[Studies on the chemical constituents of Ficus microcarpa].

OBJECTIVE: To study the chemical constituents of the Ficus microcarpa. METHODS: Isolation and identification were carried out by using various chromatography techniques and spectral methods. RESULTS: Eight compounds were isolated. Their structures were identified as beta-amyrone (I), lupeol (II), lupeol acetate (III), maslinic acid (IV), epifriedelinol (V), stearic acid (VI), beta-sitosterol (VI), daucosterol (VI). CONCLUSION: Compounds I, II, VI are isolated from this plant for the first time.

Four new minor taxanes from cell cultures of Taxus chinensis.

Four new minor taxanes (1-4) have been isolated from Ts-19 cell cultures of Taxus chinensis together with five known taxanes (5-9) by silica gel chromatography combined with semi-preparative HPLC chromatography. On the basis of the analyses of the chemical and spectroscopic (IR, MS, 1D, and 2D NMR) data, the structures of new compounds were elucidated as 5alpha-hydroxy-2alpha,10beta-diacetoxy-14beta-(3-hydroxy-2-methyl-butyryl)oxytaxa-4(20),11-diene (1), 2alpha,5alpha,10beta-triacetoxy-14beta-(2-hydroxy-propionyl)oxytaxa-4(20),11-diene (2), 2alpha,5alpha,10beta-triacetoxy-14beta-(2-hydroxy-3-methyl-butyryl)oxytaxa-4(20),11-diene (3), and 2alpha-benzoxy-4alpha,9alpha,10beta,13alpha-tetraacetoxytax-11-ene (4), respectively. Compounds 1-5 were pharmacologically evaluated for their cytotoxicities against five human cancer cell lines (HCT-8, Bel-7402, BGC-823, A549, and A2780) and their reversing activity towards multi-drug resistance A549/taxol tumor cell line, and the results showed that all of the tested compounds exhibited very low cytotoxicities, while compound 4 possessed twice the reversing activity as that of verapamil at 10 muM.

[The comparative study on morphology and polysaccharides content of Dendrobium loddigesii from different habits].

The morphological characters and the polysaccharides content of Dendrobiam loddigesii from different habits were studied in this paper. The results showed that there were remarkable differences in morphology from five areas, such as stem height and diameter, laminae sizes and figures, amount of lateral bud, and texture of stem. The content of polysaccharides from sample of Xingyi and Anlong, Guizhou Province, respectively 22. 62% and 20. 96% , were higher than that of other areas. It can be preferentially choosed as good materal on commareial production.

[ITS sequence identification of Radix Bupleuri].

OBJECTIVE: To provide the basis of molecular authentication of Radix Bupleuri by the comparison of the internal transcribed spacer (ITS) sequences of five kinds of Radix Bupleuri in common use. METHOD: Firstly, total DNA of five kinds of Radix Bupleuri was extracted. Secondly, the ITS sequence was amplified by PCR with universal primer of ITS and PCR product was directly sequenced after purification. RESULT: The length of ITS1 and ITS2 sequence was 214-220 bp and 230-231 bp respectively. There were distinct variation sites between the ITS sequences of the five kinds of Radix Bupleuri. CONCLUSION: ITS sequence may be the evidence for the molecular authentication of Radix Bupleuri.

Characterization of phenolic compounds in the Chinese herbal drug Tu-Si-Zi by liquid chromatography coupled to electrospray ionization mass spectrometry.

Phenolic compounds are the major bioactive constituents of the Chinese herbal drug Tu-Si-Zi, which is prepared from the seeds of Cuscuta chinensis. However, seeds of C. australis also are offered under the name of this drug in the herb market. In order to make a comparison of their chemical constituents, the phenolic compounds of these two Cuscuta species were analyzed by high-performance liquid chromatography/diode-array detection/electrospray ion trap tandem mass spectrometry (HPLC/DAD/ESI-MS(n)). A total of 50 compounds were observed in the methanol extracts, including 23 flavonoids, 20 lignans and 7 quinic acid derivatives. These compounds were separated on a C18 column and identified or tentatively characterized based on UV spectra and MS fragmentation behavior. In contrast to previous reports, the phenolic patterns of these two Cuscuta species were found to be very different. Kaempferol and astragalin were the predominant constituents of C. australis, while hyperoside was the major compound in C. chinensis. Most of the identified compounds, especially the acylated flavonoid glycosides, have not previously been reported from Cuscuta species. In addition, a 30 Da neutral loss observed for flavonols was investigated and could be used to differentiate flavonoid isomers such as kaempferol and luteolin. The ESI-MS fragmentation behavior of furofuran lignans was also investigated, and a characteristic pathway is proposed. The large differences observed between the phenolic constituents of C. chinensis and C. australis strongly encouraged further comparison of the bioactivities of these two species.

[Studies on the botanical sources and DNA molecular identification of Herba Asari based on ITS sequence].

OBJECTIVE: To explore the genetic basis of using three species of Asarum as Herba Asari to determine the taxonomic positions of Asarum heterotropoides and A. siebodii; and to apply DNA molecular analysis as a tool for identification of Herba Asari. METHOD: PCR, purification, sequence analysis were prerformed. RESULT: MS sequences of the three Asarum species were obtained. 3 botanical sources of Herba Asari are closely clustered together on the topology tree; one inner branch is composed of A. heterotropoides and A. sieboldii, whereas another branch contains A. sieboldii. Their ITS sequences are different. CONCLUSION: Three plant species of Herba Asari are closely related, and there are genetic reasons that they are used as the sources of the same medicine. The classification placement of A. sieboldii is not certain. The differences of ITS sequences of the botanical sources of Herba Asari can be used as a means of identification.

[Identification of Pterocephalus hookeri].

OBJECTIVE: To study the identification method of Pterocephalus hookeri. METHOD: The microscopical, Physicochemical and TLC methods were used. RESULT AND CONCLUSION: The convenient and effective identification methods for P. hookeri were established, which provide basis for its quality standard and development.

Determination of flavonoids in Semen Cuscutae by RP-HPLC.

Flavonoids contents in 40 samples of Semen Cuscutae collected from areas all around China were investigated. Five principal flavonoids, quercetin 3-O-beta-D-galactoside-7-O-beta-D-glucoside, quercetin 3-O-beta-D-apiofuranosyl-(1-->2)-beta-D-galactoside, hyperoside, quercetin and kaempferol were analyzed simultaneously by using a reversed phase liquid chromatograph system with 0.025 M phosphoric acid-methanol as mobile phase. The recovery of the method was 97.0-102.9%, and all the flavonoids showed good linearity (r > or = 0.9990) in a relatively wide concentration range. The results indicated that contents of flavonoids in S. Cuscutae varied significantly from species to species, locality to locality, and parasiting host to host. Cuscuta australis contained a much higher content of kaempferol than C. chinensis, and few flavonoids were detected in C. japonica. The quality of S. Cuscutae can be evaluated according to the contents of flavonoids.

[The influences of inorganic elements in soil on the geolism of Atractylodes lancea].

OBJECTIVE: To study the influence of inorganic elements in soil on the geolism of Atractylodes lancea. METHOD: The concentrations of 15 kinds of inorganic elements of regional A. lancea and their correspondingly soils were determined, and the data were analysed with the SPSS10.0 software. RESULT: The mean concentration of Ni in geoherbs of A. lancea was 3 times higher than that in the non-geoherbs. The accumulation of Ca is high in geoberbs. There is no relationship between the concentrations of inorganic elements in A. lancea and those in their corresponding soil. CONCLUSION: A. lancea adjusts the concentration of inorganic elements mainly by active absorption, and there are good relationship between the accumulation of Fe and Cr, Fe and Hg, Hg and Cr, As and Pb, Co and Sr.

[Studies on chemical constituents of Cuscuta chinensis].

OBJECTIVE: To study the chemical constituents of the seeds of Cuscuta chinensis. METHOD: The separation was carried out by polyamide and silica gel chromatography, and the compounds were identified by means of physico-chemical and spectroscopic methods. RESULTS: Eight compounds were isolated from the plant and identified as quercetin 3-O-beta-D-galactoside-7-O-beta-D-glucoside (I), quercetin 3-O-beta-D-apiofuranosyl-(1-->2)-beta-D-galactoside (II), hyperoside (III), isorhamnetin (IV), kaempferol (V), quercetin (VI), d-sesamin (VII) and 9(R)-hydroxy-d-sesamin (VIII). CONCLUSION: Compounds IV and VII were isolated from Cuscuta for the first time, and I, II and VIII were characteristic constituents for this vegetable drug.

[Study on the genetiey relationship between Chinese and Korean medicinal materials of niuxi with the method of RAPD].

OBJECTIVE: To study the hereditary relationship between Chinese and Korean medicinal materials of Niuxi achyranthis root. METHOD: Ten samples of four kinds of Niuxi was studied with the method of RAPD. RESULT: Expanded product showed total record of 100 spectrum bands, which proved that the hereditary gap between Korean self-produced A. japonica and A. bidentata is smallest. CONCLUSION: Korean self-produced A. japonica is near to A. Sidentata.

[A study on genetic variation between wild and cultivated populations of Paeonia lactiflora Pall].

AIM: To discuss the genetic differentiation between wild and cultivated populations of Paeonia lactiflora Pall., and to find the reason for forming the genuineness of Radix Paeoniae rubra (Chishao) and Radix Paeoniae alba (Baishao). METHODS: Forty three representative samples of P. lactiflora from 11 localities were analyzed by RAPD method with 21 random primers. According to RAPD results, the genetic diversity and genetic differentiation of P. lactiflora were detected by the percentage of polymorphic sites (PPB), the coefficient of gene differentiation (GST) and analysis of molecular variance (AMOVA). RESULTS: (1) At species level, the PPB of P. lactiflora was 85.26%, the Nei's gene diversity (Ht) was 0.166. The PPB in wild population (WP) was 77.61%, which was more than that (54.96%) in cultivated population for medicine (MP), and that (61.76%) in cultivated population for ornament (OP). (2) AMOVA showed that 29.50% of the genetic diversity resulted from differentiation among populations. Pairwise Phist distance (0.3632) between WP and MP was furthest, while that (0.0973) between MP and OP was closest, indicating population differentiation was significant (P < 0.001). (3) In general, cluster analysis revealed that the samples of P. lactiflora were divided in wild and cultivated groups (except for 39). In WP, individuals of Duolun were separated from those of other localities. In MP, the clusters of samples corresponded well with their own habitats. CONCLUSION: In addition to environmental factor, genetic differentiation should be the main cause for the genuineness of "Chishao" and "Baishao". Because of over collection and worse habitat, P. lactiflora in Duolun, whose root is the famous Chinese Geo-herbal--"Duolun Chishao", is progresively rare. So, it should become the endangered germplasm resource to protect.