Independent risk factors for true malignancy in atypical cytologic diagnostic category in EUS-FNA/FNB of the pancreas: A novel prediction model.

Background and Objects: An atypical cytologic diagnosis arises from inflammation or early neoplastic process. It is commonly found in EUS-guided fine-needle aspiration/biopsy (EUS-FNA/FNB) tissue sampling of pancreatic malignancies. The aims of this study were to evaluate the diagnostic performance of EUS-FNA/FNB in patients with cytologic diagnosis of atypical cells and to develop a prediction model for malignant tumors of the pancreas in the atypical cytologic diagnostic category. Methods: Two hundred and twenty-six patients in the atypical cytologic diagnostic category were analyzed. Multivariate logistic regression analyses were performed to determine predictive factors for pancreatic malignancies. The final diagnoses were confirmed by repeat biopsy; surgical pathology, or clinical follow-up for at least 6 months. Results: The atypical cytologic diagnosis using EUS-FNA/FNB was associated with an absolute risk of malignancy (82.3%). Multivariate logistic regression analyses revealed that older age, long axis of the mass, and increased carbohydrate antigen 19-9 (CA19-9) were independent risk factors for true malignant pancreatic tumors among patients in the atypical cytologic diagnostic category. The calibration curve had a slope of 0.96, and a regression coefficient (R2) of 0.91. The area under the receiver operating characteristic curve of the validation group was 0.803. Conclusions: Atypical lesions of EUS-FNA/FNB have a higher risk of malignancy. Older age, the long axis of the mass, and elevated serum CA19-9 level were identified as independent risk factors for true malignant pancreatic tumors among patients in the atypical cytologic diagnostic category.

Developing Push-Pull Hydroxylphenylpolyenylpyridinium Chromophores as Ratiometric Two-Photon Fluorescent Probes for Cellular and Intravital Imaging of Mitochondrial NQO1.

This work highlights the use of push-pull hydroxylphenylpolyenylpyridinium fluorophores coupled with trimethyl lock quinone to engineer the ratiometric two-photon probes for cellular and intravital imaging of mitochondrial NAD(P)H:quinone oxidoreductase 1 (NQO1), a critical antioxidant enzyme responsible for detoxifying quinones. As a typical representative, QBMP showed favorable binding with NQO1 with a Michaelis constant of 12.74 µM and exhibited a suite of superior properties, including rapid response (4 min), large Stokes shift (162 nm), ultralow detection limit (0.9 nM), favorable two-photon cross section for the released fluorophore (70.5 GM), and deep tissue penetration (225 µm) in fixed brain tissues. More importantly, this probe was successfully applied for distinguishing different NQO1-expressing cancer and normal cells, revealing decreased NQO1 activity in a cellular Parkinson's disease model, screening NQO1 inducers as neuroprotective agents, and imaging of NQO1 in live mouse brain.

Ortho-dihydroxychalcones as cupric ion-dependent prooxidants: activity and mechanisms.

The activity and chemical mechanisms of ortho-dihydroxychalcones as cupric ion-dependent prooxidants were investigated under aerobic conditions. This work confirms that 3,4,3',4'-tetrahydroxychalcone and cupric ions could synergistically advance strand breakage of plasmid DNA, but also effectively induce DNA damage and apoptosis of human hepatoma HepG2 cells under low concentrations by promoting ROS production. Interestingly, ortho-dihydroxy groups on the aromatic B ring, connected by a double bond, possess higher DNA-cleaving activity than those on the aromatic A ring directly attached to a carbonyl group. Further mechanistic investigation on the cupric ion-mediated oxidation of 3,4,3',4'-tetrahydroxychalcone, by UV/vis spectral changes, reveals that at neutral pH, electron transfer is facilitated by means of sequential proton loss from the 4'-OH on the aromatic A ring and the subsequent formation of phenolate anion-Cu(II) complexes; the resulting phenoxyl radical could undergo the second deprotonation and electron transfer to give an ortho-quinone on the aromatic B ring.

The peripheral messenger RNA expression of glycogen synthase kinase-3ß genes in Alzheimer's disease patients: a preliminary study.

OBJECTIVE: To explore the peripheral leucocytic messenger RNA (mRNA) expression of glycogen synthase kinase-3ß (GSK-3ß) gene in Alzheimer's disease (AD) patients. METHODS: Using TaqMan relative quantitative real-time polymerase chain reaction, we analyzed leucocytic gene expression of GSK-3ß in 48 AD patients and 49 healthy controls. Clinical data of AD patients were also collected. RESULTS: The mRNA expression level of the GSK-3ß gene was significantly higher in the AD group (3.13±0.62) than in the normal group (2.77±0.77). Correlational analyses showed that the mRNA expression level of GSK-3ß gene in AD patients was associated with the age of onset (P=0.047), age (P=0.055), and Behavioral Pathology in Alzheimer's Disease Rating Scale total score (P=0.062) and subscores: aggressiveness score (P=0.073) and anxieties and phobias score (P=0.067). Through multivariate regression model, older age, higher anxieties and phobias score and aggressiveness score were associated with higher mRNA expression level of GSK-3ß gene. CONCLUSION: In AD patients, the mRNA expression level of the GSK-3ß gene is increased and may be related to age and behavioural pathology in AD.

[Association of cyclic adenosine monophosphate response element-binding protein gene and major depressive disorder].

OBJECTIVE: To investigate the association between single nucleotide polymorphisms (SNPs) in cyclic adenosine monophosphate response element-binding protein(CREB1) gene and major depressive disorder (MDD). METHODS: We recruited 105 parent-offspring trios of Chinese descent, extracted whole blood genomic DNA, and genotyped the SNPs in rs10932201 and rs6740584 loci. Single-marker transmission disequilibrium test (TDT), pairwise SNP linkage disequilibrium(LD) and haplotype-based TDT were performed. RESULTS: No significant association with MDD was observed for SNPs rs10932201 and rs6740584 (P=0.1004 and P=0.4986). However, there was strong positive association between the rs10932201-rs6740584 haplotype and MDD (P=0.00003241), and both haplotypes of A-C and A-T were significantly associated with MDD (P=0.020 and P=0.00022). CONCLUSION: The rs10932201-rs6740584 haplotype of the CREB1 gene may play an important role in the pathogenesis of MDD.

Antioxidant and antiproliferative activities of hydroxyl-substituted Schiff bases.

Eight hydroxyl-substituted Schiff bases with the different number and position of hydroxyl group on the two asymmetric aromatic rings (A and B rings) were prepared by the reaction between the corresponding aromatic aldehyde and aniline. Their antioxidant effects against the stable galvinoxyl radical (GO(.)) in ethyl acetate and methanol, and 2,2'-azobis(2-amidinopropane hydrochloride) (AAPH)-induced DNA strand breakage, and their antiproliferative effects on human hepatoma HepG2 cells, were investigated. Structure-activity relationship analysis demonstrates that o-dihydroxyl groups on the aromatic A ring and 4-hydroxyl group attached to the aromatic B ring contribute critically to the antioxidant and antiproliferative activities.

Antioxidant activity of alpha-pyridoin and its derivatives: possible mechanism.

alpha-Pyridoin (1, 1,2-di(2-pyridyl)-1,2-ethenediol) is a unique enediol antioxidant. To explore the detailed antioxidant mechanism of alpha-pyridoin, we synthesized alpha-pyridoin and its 5,5'- or 6,6'-bis-substituted derivatives (2-7) and compared their capacities to scavenge galvinoxyl radical (GO*) and protect human red blood cells (RBCs) from oxidative haemolysis. It was found that the compounds (5 and 6) with a methyl or methoxy group at the 5-position exhibit significantly higher GO*-scavenging and anti-haemolysis activities than other derivatives and vitamin C. Kinetic analysis of the GO*-scavenging reaction and the effect of added base on the reaction rate revealed that in ethyl acetate, the reaction occurs primarily by the direct hydrogen atom transfer (HAT mechanism). However, in ethanol that supports ionization, the kinetics of the process is mostly governed by sequential proton loss electron transfer (SPLET mechanism).

Hydroxycinnamic acids as DNA-cleaving agents in the presence of Cu(II) ions: mechanism, structure-activity relationship, and biological implications.

The effectiveness of hydroxycinnamic acids (HCAs), that is, caffeic acid (CaA), chlorogenic acid (ChA), sinapic acid (SA), ferulic acid (FA), 3-hydroxycinnamic acid (3-HCA), and 4-hydroxycinnamic acid (4-HCA), as pBR322 plasmid DNA-cleaving agents in the presence of Cu(II) ions was investigated. Compounds bearing o-hydroxy or 3,5-dimethoxy groups on phenolic rings (CaA, SA, and ChA) were remarkably more effective at causing DNA damage than the compounds bearing no such groups; furthermore, CaA was the most active among the HCAs examined. The involvement of reactive oxygen species (ROS) and Cu(I) ions in the DNA damage was affirmed by the inhibition of the DNA breakage by using specific scavengers of ROS and a Cu(I) chelator. The interaction between CaA and Cu(II) ions and the influence of ethylenediaminetetraacetic acid (EDTA), the solvent, and pH value on the interaction were also studied to help elucidate the detailed prooxidant mechanism by using UV/Vis spectroscopic analysis. On the basis of these observations, it is proposed that it is the CaA phenolate anion, instead of the parent molecule, that chelates with the Cu(II) ion as a bidentate ligand, hence facilitating the intramolecular electron transfer to form the corresponding CaA semiquinone radical intermediate. The latter undergoes a second electron transfer with oxygen to form the corresponding o-quinone and a superoxide, which play a pivotal role in the DNA damage. The intermediacy of the semiquinone radical was supported by isolation of its dimer from the Cu(II)-mediated oxidation products. Intriguingly, CaA was also the most cytotoxic compound among the HCAs toward human promyelocytic leukemia (HL-60) cell proliferation. Addition of exogenous Cu(II) ions resulted in an effect dichotomy on cell viability depending on the concentration of CaA; that is, low concentrations of CaA enhanced the cell viability and, conversely, high concentrations of CaA almost completely inhibited the cell proliferation. On the other hand, when superoxide dismutase was added before, the two stimulation effects of exogenous Cu(II) ions were significantly ameliorated, thus clearly indicating that the oxidative-stress level regulates cell proliferation and death. These findings provide direct evidence for the antioxidant/prooxidant mechanism of cancer chemoprevention.

Radical-scavenging activity and mechanism of resveratrol-oriented analogues: influence of the solvent, radical, and substitution.

Resveratrol (3,5,4'-trihydroxy-trans-stilbene, 3,5,4'-THS) is a well-known natural antioxidant and cancer chemopreventive agent that has attracted much interest in the past decade. To find a more active antioxidant and investigate the antioxidative mechanism with resveratrol as the lead compound, we synthesized 3,5-dihydroxy-trans-stilbene (3,5-DHS), 4-hydroxy-trans-stilbene (4-HS) 3,4-dihydroxy-trans-stilbene (3,4-DHS), 4,4'-dihydroxy-trans-stilbene (4,4'-DHS), 4-hydroxy-3-methoxy-trans-stilbene (3-MeO-4-HS), 4-hydroxy-4'-methoxy-trans-stilbene (4'-MeO-4-HS), 4-hydroxy-4'-methyl-trans-stilbene (4'-Me-4-HS), 4-hydroxy-4'-nitro-trans-stilbene (4'-NO(2)-4-HS), and 4-hydroxy-4'-trifluoromethyl-trans-stilbene (4'-CF(3)-4-HS). The radical-scavenging activity and detailed mechanism of resveratrol and its analogues (ArOHs) were investigated by the reaction kinetics with galvinoxyl (GO(*)) and 2,2-diphenyl-1-picrylhydrazyl (DPPH(*)) radicals in ethanol and ethyl acetate at 25 degrees C, using UV-vis spectroscopy. It was found that the reaction rates increase with increasing the electron-rich environment in the molecules, and the compound bearing o-dihydroxyl groups (3,4-DHS) is the most reactive one among the examined resveratrol analogues. The effect of added acetic acid on the measured rate constant for GO(*)-scavenging reaction reveals that in ethanol that supports ionization solvent besides hydrogen atom transfer (HAT), the kinetics of the process is partially governed by sequential proton loss electron transfer (SPLET). In contrast to GO(*), DPPH(*) has a relatively high reduction potential and therefore enhances the proportion of SPLET in ethanol. The relatively low rate constants for the reactions of ArOHs with GO(*) or DPPH(*) in ethyl acetate compared with the rate constants in ethanol prove that in ethyl acetate these reactions occur primarily by the HAT mechanism. The contribution of SPLET and HAT mechanism depends on the ability of the solvent to ionize ArOH and the reduction potential of the free radical involved. Furthermore, the fate of the ArOH-derived radicals, i.e., the phenoxyl radicals, was investigated by the oxidative product analysis of ArOHs and GO(*) in ethanol. The major products were dihydrofuran dimers in the case of resveratrol, 4,4'-DHS, and 4-HS and a dioxane-like dimer in the case of 3,4-DHS. It is suggested from the oxidative products of these ArOHs that the hydroxyl group at the 4-position is much easier to subject to oxidation than other hydroxyl groups, and the dioxane-like dimer is formed via an o-quinone intermediate.

Antioxidant-based lead discovery for cancer chemoprevention: the case of resveratrol.

Resveratrol is a well-known natural antioxidant and cancer chemopreventive agent that has attracted much interest in the past decade. Resveratrol-directed compounds were synthesized, and their antioxidant effects against reactive oxygen species (ROS)-induced DNA damage, their prooxidant effects on DNA damage in the presence cupric ions, and their cytotoxic and apoptosis-inducing effects on human promyelocytic leukemia (HL-60) cells were investigated in vitro. It was found that the compounds bearing o-diphenoxyl groups exhibited remarkably higher activities in inhibiting ROS-induced DNA damage, accelerating DNA damage in the presence cupric ions, and inducing apoptosis of HL-60 cells compared with the ones bearing no such groups. The detail mechanism of the structure-activity relationship was also studied by the oxidative product analysis of resveratrol and its analogues with galvinoxyl radical or cupric ions and UV-visible spectra change in the presence cupric ions. This study reveals a good and interesting correlation between antioxidant and prooxidant activity, as well as cytotoxicity and apoptosis-inducing activity against HL-60 cells, and provides an idea for designing antioxidant-based cancer chemoprevention agents.

4,4'-Dihydroxy-trans-stilbene, a resveratrol analogue, exhibited enhanced antioxidant activity and cytotoxicity.

Resveratrol (3,5,4'-trans-trihydroxystibene) is a natural phytoalexin present in grapes and red wine, which possesses a variety of biological activities including antioxidant activity. In order to find more active antioxidant with resveratrol as the lead compound we synthesized 4,4'-dihydroxy-trans-stilbene (4,4'-DHS). The antioxidant activities of resveratrol and 4,4'-DHS were evaluated by the reaction kinetics with galvinoxyl radical or Cu(II) ions, and the inhibition effects against free-radical-induced peroxidation of human erythrocyte ghosts. It was found that 4,4'-DHS exhibits remarkably higher antioxidant activity than resveratrol. The oxidative products of resveratrol and 4,4'-DHS in the presence of Cu(II) in acetonitrile were identified as the dihydrofuran dimers by spectroscopic method, and the antioxidant mechanism for 4,4'-DHS was proposed. In addition, 4,4'-DHS exhibits remarkably higher cytotoxicity against human promyelocytic leukemia (HL-60) cells than resveratrol.

[Association between depression and G72 gene polymorphism].

OBJECTIVE: To investigate the association between G72 gene polymorphisms and depression,and to probe the difference of G72 gene polymorphisms between depression with and without mixed family history. METHODS: The polymorphisms of G72 gene (rs947267 and rs2181953) were detected by PCR technique in 100 depressive patients without mixed family history, 50 depressive patients with mixed family history and 86 normal controls. RESULTS: (1) The frequencies of rs947267 genotypes and alleles in female depressive patients without mixed family history were significant different to the controls (P=0.017 and P=0.008), the OR scores were 0.300 (A/A, P=0.010), 0.456(A, P=0.008) and 2.195(C, P=0.008) respectively; but in male patients there were no significant differences to the controls (P>0.05). (2) The frequencies of rs2181953 genotypes and alleles in the depressive patients without mixed family history were not significantly different to the controls regardless of sex (P>0.05). (3) The frequencies of rs947267 and rs2181953 genotypes and alleles in the depressive patients with mixed family history were not significantly different to the controls regardless of sex (P>0.05). CONCLUSION: The G72 gene polymorphism may be associated with female depressive patients without mixed family history,C allele of rs947267 may be the risk factor.

[Expression levels of APP and PS1 genes in patients with Alzheimer's disease].

The gene expression levels of amyloid precursor protein (APP) and presenilin 1 (PS1) in the peripheral blood samples of patients with Alzheimer's disease(AD) and their association with the disease were studied. The absolute expression levels of APP and PS1 genes were quantified in 45 AD patients, 25 patients with vascular dementia (VD) and 60 healthy controls by real-time quantitative PCR using SYBR Green I. The APP expression levels in healthy controls, AD cases and VD cases are 0.026+/-0.005, 0.044+/-0.006 and 0.072+/-0.013 amol/microg cDNA, respectively; and the PS1 expression levels are 0.026+/-0.004, 0.051+/-0.011 and 0.039+/-0.005 amol/microg cDNA, respectively. Both APP and PS1 expression levels were significantly elevated in AD or in VD cases (APP, AD vs Control, t=2.639, P<0.01, VD vs Control, t=3.028P<0.01; PS1, AD vs Control, t=2.173P<0.05, VD vs Control, t=2.012P<0.05). It seems that elevated APP and PS1 gene expression is associated with dementia but not especially with AD.

[Genome-wide search for linkage to attention deficit hyperactivity disorder (ADHD) on the X chromosome].

Attention deficit hyperactivity disorder (ADHD) is the most common childhood-onset behavioral. Boys are more often affected than girls. Family, twin and adoption studies have supported a strong genetic basis. The etiology of this disorder is not clear. Molecular genetic and pharmacological studies suggest the involvement of dopaminergic and noradrenergic neurotransmitter systems in ADHD, e.g , Several reports have found association between ADHD and the dopamine receptor gene DRD-4.the dopamine transporter gene DAT1, and the catechol-o-methyltransferase. Our previous studies showed an association between ADHD and the DXS7 locus, which is located in closely linked to the MAO gene, and MAOA gene on chromosome X. To test this hypothesis, we used the genome scan for a predisposing locus on chromosome X to ADHD. We used the tramsmission/disequilibrium test (TDT) to test for linkage between a VNTR polymorphism at the 48 markers of chromosome X and DSM-III-R oliagnosed ADHD in 84 nuclear families of the Chinese population. The TDT analysis revealed linkage between ADHD and the DXS1214(TDT: Chi2=18.1, df=7, P<0.01), DXS8102(TDT: Chi2=7.9, df=3, P<0.05), DXS1068(TDT: Chi2=21.9, df=9, P<0.01), DXS8015(TDT: Chi2=14.6, df=7, P<0.05), DXS1059(TDT: Chi2=27.8, df=10, P<0.01) and DXS8088(TDT: Chi2=20.4, df=3, P<0.01).The data showed that susceptibility loci might reside in chromosome Xp11.4-Xp21 and Xq23 for ADHD.

No association between attention-deficit hyperactivity disorder and catechol-O-methyltransferase gene in Chinese.

Previous studies suggested that the catecholaminergic systems may be involved in the pathogenesis of attention-deficit hyperactivity disorder(ADHD). Since catechel-O-methyltransferase (COMT) is an enzyme involved in the degradation of catecholaminergic neurotransmitters of the dopaminergic and noradrenergic systems,it is possible that COMT may play a role in ADHD. To test this hypothesis, we used two family-based analyses,the transmission disequilibrium test (TDT) and the haplotype-based haplotype relative risk (HHRR), to examine the possible association between COMT gene and DSM-IV-diagnosed ADHD in a Chinese sample consisting of 79 ADHD probands and their parents. Both TDT (chi2 = 1.03, df=1, P > 0.05) and HHRR (chi2 = 1.08, df = 1, P > 0.05) analyses failed to detect preferential transmission of a COMT allele to the ADHD children. Our data suggested that there was no association between ADHD and the COMT gene in the Chinese population.

[A study on the relation between the apolipoprotein E promoter -427C/T polymorphism and Alzheimer's disease].

OBJECTIVE: To determine the relation between the apolipoprotein E(apoE) promoter -427C/T polymorphism and Alzheimer's disease (AD) in a Chinese Han population in Shanghai. METHODS: The apoE promoter -427C/T polymorphism in 104 AD cases and 110 healthy subjects was detected using polymerase chain reaction method and restriction fragment length polymorphism genotyping technique. The differences in polymorphic distribution between the two groups were tested, and odds ratio was computed. RESULTS: No differences in apoE -427C/T genotypic distribution were observed between AD cases and controls (P>0.05). Even after stratification according to apoE epsilon 4 stratum, there was not any polymorphic distribution difference when epsilon 4 carriers or non epsilon 4 carriers were compared with controls (P>0.05). The association between AD and apoE epsilon 4 appeared in the TT group(OR=3.94,95%, CI:22067038, chi-square=21.48, P<0.05), but not in CT or CC group. CONCLUSION: ApoE -427C/T polymorphism was not a susceptibility factor for AD in this Han population in Shanghai.

[Expression variation and mutation analysis of exon 9 and 10 in amyloid precursor protein gene in Alzheimer's disease].

To explore the expression differences of exon 9 and 10 in Amyloid Precursor Protein gene(APP9 approximately 10) in Alzheimer's disease,and detect the probable point mutation appeared in cDNA fragment of APP9 approximately 10 in the Shanghai Han people.semi-quantitative competitive RT-PCR technique was performed to detect the expression of APP9 approximately 10 in peripheral lymphocyte, and the Apolipoprotein E gene(ApoE) and Presenilin 1(PS1)gene were genotyped with PCR-RFLP method. We also analyzed the point mutation in APP9 approximately 10 cDNA through the denatured gel electrophoresis. The results are as follows:1. While compared with healthy controls,expression of APP9 approximately 10 mRNA was significantly enhanced in Alzheimer disease; 2.APOE*epsilon4 allele, the most common genetic risk factor for AD, did not affect the Expression of APP9 approximately 10 mRNA, whereas the APP9 approximately 10 mRNA expression might be increased by the allele 1 of PS1 gene, another probable susceptibility gene of AD.3. No point mutation in APP9 approximately 10 cDNA was detected. In our samples, the expression of APP9 approximately 10 mRNA in AD was significantly different from that of controls, suggesting that the change of peripheral APP9 approximately 10 mRNA expression might be another bio-marker used in clinical diagnosis for AD.