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Recently, new cationic antibacterial peptide OM19R has been designed with low minimum inhibitory concentration (MIC) values against some gram-negative bacteria, such as Escherichia coli, Salmonella, and Shigella. However, this hybrid peptide, like most antibacterial peptides, has low enzyme stability and short half-life, which, in turn, increases the drug's cost. In this study, an antibacterial peptide (OM19r-8) was obtained containing some D-Arg amino acids. The new preparations were carried out through the replacement of l -Arginine by d -Arginine and the addition of PEG chains. Firstly, eight OM19r series of antibacterial peptides were obtained by designing D-Arg. Then, a polyethylene glycol-modified product mPEG5-butyrALD-OM19r-8 (mPEG5-OM19r-8) was isolated and purified by reverse-phase high-performance liquid chromatography (RT-HPLC). The enzyme stability test showed that the resistance of antibacterial peptide OM19r-8 to protease degradation increased by 4-32-fold. Moreover, the Time-kill studies showed that the germicidal kinetics curves of mPEG5-OM19r-8 and OM19r-8 to Escherichia coli had a similar trend, thus suggesting that PEG modification has an acceptable effect on the activity of the original peptide. Furthermore, the elimination of half-life (28.09 ± 2.81min) of mPEG5-OM19r-8, and the area under the drug concentration-time curve (2686.48 ± 651.36min∗ug/ml) was significantly prolonged. The current study demonstrates an example that optimizes the AMP by utilizing L-to-D amino acid replacement and including PEG chains. These results provide useful data for the clinical application of the mPEG5-OM19r-8.

To investigate the effects of genipin on promoting brown adipose tissue activation and white adipose tissue browning.The male C57BL/6J mice were divided into three groups: normal control group, genipin group and cold-stimulus group.Genipin group were treated consecutively with genipin at a dose of 15 mg/kg once a day for 9 days, normal control group were treated with the saline.The mice with cold-stimulus were exposed to 4℃ environment for 5 days.Daily food amount and body weight were measured.Morphological changes were observed in the subscapular region, inguinal region and epididymis around the adipose tissue.The expression of uncoupling protein 1 (UCP1) was determined by real-time PCR and Western blot respectively.The wet weight of white fat in genipin-treated mice was decreased by 16% , and 28% in that of cold-stimulus mice, compared with the normal control group (P＜0.05).After treatments of genipin and cold-stimulus, the color of white adipose tissues was darker, and the size of lipid droplets in adipocytes was smaller, whereas the number was increased.Compared with the normal control group, UCP1 expression was increased obviously in fat tissues, including the subcutaneous and visceral white adipose tissues, and brown adipose tissue after treated with genipin and cold-stimulus (P＜0.05).Genipin promoted activation of brown adipose tissue and browning of white adipose tissue by upregulating UCP1 expression, which could contribute to the loss of body weight against obesity.

To investigate the relationship between serum phospholipid omega-3 polyunsaturated fatty acids (ω-3 PUFAs) and insulin resistance (IR) in patients with type 2 diabetes mellitus (T2DM) and non-alcoholic fatty liver disease (NAFLD).51 patients with T2DM and NAFLD (T2DM+NAFLD group), 50 with T2DM alone (T2DM group), 45 with NAFLD alone (NAFLD group), and 42 healthy control subjects (NC group) were studied. Serum ω-3 PUFA profiles were analyzed by gas chromatography, and alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyltransferase (GGT), and serum lipid concentrations were measured. Insulin resistance was assessed by the homeostasis model assessment method (HOMA-IR).HOMA-IR levels were higher in the T2DM+NAFLD group than in the T2DM, NAFLD and NC groups (p0.05), as were ALT, AST, GGT, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG) concentrations (p0.05). Conversely, serum ω-3 PUFA levels were significantly lower in the T2DM+NAFLD group than in the other groups (p0.05). The ω-3 PUFA level was negatively correlated with HOMA-IR, TC, LDL-C and TG.Serum phospholipid ω-3 PUFA levels were significantly decreased in patients with T2DM and NAFLD, and were negatively related with insulin resistance. Thus, reduced ω-3 PUFAs may play an important role in the development of T2DM and NAFLD.

To investigate the effects of inspiratory muscle training followed by non-invasive positive pressure ventilation in patients with severe chronic obstructive pulmonary disease (COPD).This investigator-initiated randomized, controlled trial recruited 88 patients with stable GOLD stage IV COPD, who were randomized into 4 equal groups to continue oxygen therapy (control group) or to receive inspiratory muscle training followed by non-invasive positive pressure ventilation (IMT-NPPV group), inspiratory muscle training only (IMT group), or noninvasive positive pressure ventilation only (NPPV group) for at least 8 weeks. The outcomes of the patients were assessed including the quality of life (SRI scores), maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP), dyspnea (MRC scores), 6-min walking distance (6MWD) and lung function.s Compared to baseline values, SRI scores, 6MWT and MRC scores increased significantly after 8 weeks in IMT-NPPV, IMT and NPPV groups, and the improvements were significantly greater in IMT-NPPV group than in IMT and NPPV groups (P0.05 for all). In IMT-NPPV and IMT groups, MIP and MEP increased significantly after the training (P0.05), and the improvement was more prominent in IMT-NPPV group (P0.05). No significant changes were found in pulmonary functions in the groups after 8 weeks of treatment (P0.05).Inspiratory muscle training followed by non-invasive positive pressure ventilation, compared with inspiratory muscle training or non-invasive positive pressure ventilation alone, can better enhance the quality of life, strengthen the respiratory muscles, improve exercise tolerance and relieve the dyspnea in patients with COPD.

It mainly discusses the high-end customer relationship profitability in the Retail Banking, the Pareto/NBO model was applied to measure the potential of customer relationship profitability, then propose the method of CRP measurement based on Pareto/NBO model, and verified the feasibility and effectiveness of the method of CRP measurement. The result is used for subdividing the high-end customer relationships in the Retail Banking.

To study influence of temperature and concentration of the polishing solution and the workpiece’s diving depth and spatial orientation in the polishing solution on electrolysis and plasma polishing, orthogonal experiments consisting of four factors at four different levels were performed by using surface roughness of the specimen after 5 minutes of polishing and electric current density in the process of the polishing as experimental indexs based on the polishing mechanism and the mathematic model of surface roughness with polishing time. Primary and secondary order and regularity of the factors affecting the roughness and the electric current density are obtained by means of extreme difference method combined with variance analytic method. Optimal parameter combination focusing on the polishing effects or considering fully the polishing effects, cost and efficiency is proposed.

In the absence of template and surfactant, hierarchical nanostructured boehmite was synthesized via a simple solvothermal route using aluminum nitrate as aluminum source and isopropanol–toluene mixture as solvent. The crystal structures, morphologies and textural properties of products were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and N 2 adsorption–desorption technique. The as-obtained hierarchical nanostructures consist of nanosheets keeping Brunauer–Emmett–Teller (BET) specific surface area and pore volume of ca. 264.7 m 2 /g and 1.2 cm 3 /g, respectively. The experimental results show that the longer reaction time and the lower reaction temperature are unfavorable to the formation of hierarchical nanostructures. Moreover, the properties of solvent have important influence on the morphology of product. The possible formation mechanism of boehmite hierarchical nanostructures was proposed and discussed.

Single ion conducting polymer electrolytes synthesized through a copolymer poly(lithium 2-acrylamido-2-methylpropanesulfonic acid-co-vinyl triethoxysilane) and a crosslinker poly(etheylene glycol) dimethacrylate (PEGDMA) were prepared. Scanning electron microscope (SEM) was used to observe the morphology of the surface and cross-section of the polymer electrolyte membrane. AC impedance and linear sweep voltammetry were used to investigate the electrochemical properties of the polymer electrolytes. It was found that the obtained membrane had a typical amorphous structure and possessed a smooth surface. The bulk resistance of the polymer electrolyte increased with the increase in the plasticizer uptake. The electrochemical stability increased with the increase in the content of VTES.

A B S T R A C T Through exploring the reaction parameters during the synthesis of the AACH, rod-like ammonium aluminium carbonate hydroxide (AACH) with high crystallinity has been successfully prepared via a facile hydrothermal method. The synthesis parameters like time, the molar ratio of NH4HCO3/Al and the properties of starting materials were systematically investigated. The structure was characterized using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), IR and transmission electron microscopy (TEM). The experimental results display that the obtained g-Al2O3 materials possess meso/ macroporosity and large pore volume, which are mainly attributed to the removal of gas molecules during the decomposition of AACH. Moreover, using the rod-like AACH as precursor, g-Al2O3 nanorods were obtained via a low-temperature thermal decomposition method.

Electrolysis and plasma polishing(EPP) is a new “green” technique that can efficiently polish metal workpieces and provide high-quality surface of the workpieces. In this paper, mechanism of EPP and why metal parts can be polished by EPP are expounded on by Streamer theory. EPP is a dynamic process consisting of oxidation and discharge. A precondition of EPP is that the removal rate of discharge is faster than oxidation. It is deduced from the mechanism and demonstrated experimentally that the material removal rate is direct proportion to the electric current density.

Activin, a member of the TGF-beta superfamily, inhibits the proliferation of breast cancer cells. Activin interacts with its type I and type II receptors to induce phosphorylation of intracellular signaling molecules known as Smads. Previous studies showed that mouse ARIP2 can reduce activin signaling by interacting with activin type II receptors (ActRIIs); however, the activity of ARIP2 in breast cancer is still unclear. In this study, we used RT-PCR to obtain a human homologue of mouse ARIP2, human activin receptor-interacting protein 2 (hARIP2). Like murine ARIP2, hARIP2 has a PDZ domain in its NH2-terminal region and can interact specifically with ActRIIs. Overexpression of hARIP2 reduced activin-induced transcriptional activity and enhanced cell proliferation and colony formation in human breast adenocarcinoma MCF-7 cells and MDA-MB-231 cells. However, down-regulation of hARIP2 expression by RNAi enhanced activin-induced transcriptional activity and reduced cell proliferation and colony formation. Immunohistochemistry revealed that hARIP2 was expressed more frequently and much more intensely in malignant breast tissues such as simple carcinoma, invasive ductal carcinoma and mucinous adenocarcinoma than in benign hyperplasia or fibroadenoma cases. These results suggest that hARIP2 is a putative growth-promoting factor involved in breast tumorigenesis and tumor development.

To study the diagnostic value of (18)F-FDG-PET/CT in multiple myeloma (MM).A total of 66 patients, who were highly suspected of MM in our hospital from July 2012 to December 2014, were chosen as study objects. All patients were diagnosed or excluded by pathological examination. All patients were detected by (18)F-FDG-PET/CT, and its diagnostic value was analyzed. The number of focuses were counted.Out of 66 patients 59 patients (89.39%) were diagnosed with multiple myeloma. The sensitivity of PET was 98.31%, the specificity of PET was 85.71%, the Youden index was 0.8402; the sensitivity of CT was 96.61%, the specificity of CT was 85.71%, the Youden index was 0.8232; the sensitivity of PET/CT was 100.00%, the specificity of PET/CT was 83.33%, the Youden index was 0.8333. In 59 MM patients, 635 focuses were detected, out of them 572 focuses (90.08%) were detected by CT, 593 focuses (93.39%) were detected by PET, 530 focuses (83.46%) were coincided on PET/CT.(18)F-FDG-PET/CT has diagnostic value for multiple myeloma, and it can be used in locating and counting focuses, as well as in evaluating the treatment efficacy and guiding the clinical work.

Studies have shown that SCC-S2 can be detected in cancer cells, but its relation with thyroid cancer remains uncertain. In the current study, we investigated SCC-S2 expression in thyroid cancer from the immune cell perspective and tumor tissue perspective. Levels of SCC-S2 in CD4+ T cells, CD8+ T cells, monocytes, natural killer (NK) T cells, tumor tissues, and adjacent noncancerous thyroid tissues were tested by real-time reverse transcription PCR and Western blot. Results revealed that mRNA and protein levels of SCC-S2 were significantly increased in peripheral CD4+ (mRNA, 1.90-fold; protein, 1.55-fold) and CD8+ T cells (mRNA, 2.37-fold; protein, 1.72-fold) but not monocytes and NKT cells in patients than in healthy donors. Further elevated mRNA level but not protein expression was observed in tumor-infiltrating CD4+ T cells, whereas both mRNA level and protein expression were further increased in tumor-infiltrating CD8+ T cells. Also, mRNA and protein levels of SCC-S2 in thyroid tissues were significantly elevated than those in adjacent noncancerous thyroid tissues. Moreover, patients with cervical lymph node metastasis presented clearly higher mRNA and protein expression of SCC-S2 compared to those without cervical lymph node metastasis (p

MicroRNAs (miRNAs) control gene expression by destabilizing target transcripts and inhibiting their translation. Aberrant expression of miRNAs has been described in many human diseases, including schizophrenia. However, the effects on miRNA expression in response to antipsychotic treatment in peripheral circulation have not been thoroughly examined.Using quantitative real-time PCR (qRT-PCR), We quantified the expression of seven candidate miRNAs in plasma samples of 40 first-episode schizophrenics before and after antipsychotic treatment. The patients were all treated with risperidone and achieved remission in 1 year.Compared with the baseline, the expression levels of miR-365 and miR-520c-3p were significantly down-regulated after 1 year of risperidone treatment (P0.001). There were no significant correlations between the clinical symptoms and the expression levels of these two miRNAs (P0.05).This study analyzed possible circulating miRNAs in response to antipsychotic monotherapy for schizophrenia, the further mechanism need to be confirmed.

Xiaomei Pan, Dong Duan, Yuquan Zhu, Hua Pang, Lili Guan, Zhixiang Lv Department of Nuclear Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China Objective: The aim of this study is to investigate the use of 99mTc-methoxyisobutylisonitrile (MIBI) imaging for evaluating the treatment response of differentiated thyroid cancer (DTC) after the first administration of a high dose of 131I.Methods: Patients with DTC who received 131I therapy underwent 99mTc-MIBI imaging after successive increases in the therapeutic dose of 131I, and the serum levels of thyroglobulin (Tg) were measured.Results: A total of 191 patients were enrolled in the final analysis, including 65 metastases and/or thyroid remnant-positive patients (22 patients with metastases and 43 patients with thyroid remnants). The sensitivity of 99mTc-MIBI imaging for detecting positive cases and thyroid remnants was 56.9% and 39.5%, respectively, which was significantly lower than that of 131I imaging (92.3% and 100%, respectively, P0.05). The Tg levels in the positive group were significantly higher than that in the negative group (P

Nucleophosmin plays a critical role in embryonic development. This study aimed to examine the expression pattern of nucleophosmin in glandular epithelium of human endometrium during the menstrual cycle.Endometrial tissues used for this study were obtained from 46 non-pregnant patients who underwent hysterectomy which had been performed to treat benign diseases. Nucleophosmin expression was assessed by in situ hybridization and immunohistochemistry.At the early-, mid- and late-proliferative phase, nucleophosmin mRNA was highly expressed in glandular epithelium of human endometrium. At the secretory phase, the expression of nucleophosmin mRNA was reduced in glandular epithelium in early-secretory phase, and the expression in mid- and late-secretory phases was not detected. Similarly, nucleophosmin protein was strongly expressed in endometrial glands throughout the proliferative phase, but was gradually reduced during secretory phase.Nucleophosmin mRNA and protein are expressed in glandular epithelium of human endometrium throughout the menstrual cycle.

To investigate the relationship between serum omega-3 polyunsaturated fatty acid (omega-3PUFA) and insulin resistance (IR) in patients with type 2 diabetes mellitus and non-alcoholic fatty liver disease (NAFLD).This trial involved 51 patients of type 2 diabetes mellitus with NAFLD (G4 group), 50 patients of type 2 diabetes alone (G3 group), 45 patients of NAFLD alone (G2 group) and 42 healthy control subjects (G1 group). Serum omega-3PUFA profile was analyzed with capillary gas chromatography. Insulin resistance was assessed by homeostasis model assessment (HOMA-IR). ALT, AST, gamma-glutamyltransferase (GGT) and serum lipids were measured.The levels of HOMA-IR were higher in G4 group than those in G3, G2 and G1 group (4.90 + or - 2.54 vs 2.38 + or - 1.23, 2.20 + or - 1.15, 1.13 + or - 0.42; P0.05). The level of ALT, AST, GGT, TC, TG, LDL-C were higher in G4 group than those in G3, G2 and G1 group (P0.05). The level of omega-3PUFA was significantly lower in G4 group than those in G3, G2 and G1 group (5.68 + or - 2.02 vs 7.17 + or - 2.38, 6.97 + or - 2.32, 10.08 + or - 2.76; P0.05). omega-3PUFA concentration was negatively correlated with HOMA-IR, TC, TG and LDL-C (r = -0.491, -0.376, -0.462, -0.408, P0.05).Serum omega-3PUFA is significantly decreased in patients with type 2 diabetes mellitus and NAFLD. Serum omega-3PUFA is negatively correlated with insulin resistance. omega-3PUFA plays a very important role in the development of diabetes mellitus and NAFLD.

To investigate the association of 5-HT(2A) receptor gene (HTR2A)-1438A/G, Catechol-O-methyltransferase (COMT) gene Val158Met, Monoamine oxidase A ( MAOA ) gene 30 bp-VNTR(MAOA-uVNTR)polymorphisms, and the educational attainment level of the parents with the intelligence of attention deficit hyperactivity disorder (ADHD) in China.A total of 485 DSM-IV ADHD children of Chinese Han descent were included, both complete IQ evaluation, HTR2A-1438A/G, COMT gene Val158Met, and MAOA-uVNTR genotyping results were obtained. The quantitative traits of psychometric IQ were calculated by using the Chinese Wechsler Intelligence Scale for Children (C-WISC). The multifactor linear regression analysis was used to test the associated factors on intelligence.Analyses revealed that ADHD children with low enzymatic activity (3R for males, 3R3R for females) of MAOA-uVNTR performed better on Full Scale IQ (FIQ) than did patients with high enzymatic activity (4R for males, 3R4R/4R4R for females) [(102.6+/-12.4) vs (100.3+/-11.7), P=0.078]. The patients with high-enzymatic activity (ValVal) of COMT gene Val158Met performed significantly better on FIQ than did patients with mid-low enzymatic activity (ValMet and MetMet)[(103.5+/-13.6) vs (100.5+/-11.5), P=0.036]. ADHD children with GG genotype of HTR2A-1438A/G performed significantly better on some aspects of C-WISC test (Full Scale IQ and Verbal Scale IQ) than did children with GA and AA genotypes [FIQ :(106.9+/-10.7) vs (100.7+/-12.3) vs (101.7+/-12.9), P=0.003; VIQ: (110.1+/-10.6) vs (103.5+/-12.1) vs (105.1+/-13.2), P=0.001]. The educational attainment level of the parents was associated with all the aspects of C-WISC test (Full Scale IQ, Verbal Scale IQ, and Performance Scale IQ). The multiple linear regression analysis showed that the genotype of HTR2A-1438A/G had significant correlation with FIQ, VIQ and PIQ; while the educational attainment level of the mother had significant correlation with FIQ and VIQ.The HTR2A-1438A/G polymorphism and the educational attainment level of the mother were associated with the intelligence of ADHD children in China.

To explore the inhibiting effect of human papillomavirus 16 E6-specific small interfering RNA (siRNA) on cervical cancer transplanted in nude mice.CaSki cells transfected with HPV16 E6 siRNA were transplanted into nude mice. HPV16 E6 siRNA was injected into the tumor, and the control group was treated with NS. Tumor growth was monitored once every other day. Terminal deoxynucleotide transferase-mediated dUTP nick end labeling (TUNEL) was performed to detect apoptosis. The expression of E6 and p53 protein was assessed by immunohistochemistry. The contents of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured and the liver and kidney were examined by histopathology.Inhibition of tumor growth was demounstrated after treatment with HPV16 E6 siRNA. The volume and weight of tumors were significantly decreased in comparison with those of control group (P0.05). Apoptosis occurred more frequently in the experiment group than in the control. The expression of E6 and p53 was down-regulated. The contents of ALT and AST underwent no significant changes, and the histopathology of liver and kidney showed no abnormal changes.The growth ability of human cervical cancer xenograft tumors in nude mice can be inhibited by HPV16 E6-specific siRNA, with no toxic side effect on the liver. It may provide an useful method of gene-therapy against cervical cancer.

To observe whether human papillomavirus 16 (HPV16) E6-specific small interfering RNAs (siRNAs) can be employed to inhibit the growth of cervical cancer cell line, and to investigate the associated mechanism.RNAi was performed using synthetic small interfering RNAs transferred into CaSki cell line by lipofectamine. The cell growth curves, live cell ratio and inhibition ratio of cells were measured by using cell counting. At various time points of post-transfection, the distributions of cell cycle, the expression levels of HPV16 E6, p53, p21 mRNA and proteins were detected by using flow cytometry (FCM) and real-time quantitative reverse transcription-polymerase chain reaction (real-time RT-PCR).The growth inhibition of E6 siRNA to CaSki cells was demonstrated after cells treated with E6 siRNA. No substantial G1 arrest was observed by FCM analysis. For 24 hours after cell transfection, the level of E6 mRNA was decreased by 20. 11 folds compared with control (P0.05). However, p53 and p21 mRNA levels appeared unaffected. 48 hours after cell transfection, the expression level of E6 protein was efficiently decreased, but the P53 and P21 protein levels increased in comparison.The inhibitory effect of HPV16 E6 siRNA to CaSki cell maybe due to specially and efficiently silence E6 mRNA expression, decrease the degradation of wild type P53 protein, and then recover the function activity of P53 protein.

To observe the effect of HPV16E7 specific expression vector on cell proliferation in cervical carcinoma SiHa cells.The HPV16E7 siRNA expression vector and empty expression vector were transfected into SiHa cells by liposome. The effects on E7 mRNA and E7 protein expression, cell cycle phase and cell growth rate were examined respectively by real-time RT-PCR, FCM and MTT assay.The HPV16E7 siRNA expression vector significantly inhibited the expression levels of E7 mRNA and E7 protein, the inhibition rates being 92.15% and 84.30% respectively. It also inhibited the transition from G, phase to S phase and the growth of SiHa cell line.HPV16E7 specific siRNA expression vector could specifically and efficiently inhibit the expression of E7 gene and hence it could regulate cell cycle and inhibit cell proliferation in cervical carcinoma SiHa cells. siRNA expression vector

To study age distribution of attention deficit hyperactivity disorder (ADHD) comorbidities in a relatively large sample, and exam the hypothesis of bad prognosis for ADHD.Using semi-structured clinical diagnosis interview scale, we investigated comorbidities of 1,002 ADHD children and adolescents from psychiatric out-patient clinic, and compared comorbidity frequency in 4 age groups.The comorbidity frequencies of disruptive behavior disorder (DBD), mood disorder, tics disorder and learning disorder (LD) in different age groups of ADHD patients differed significantly (P0.01). DBD and mood disorder in the age group of 12-14 years (124 cases,51.5%;18 cases,7.5%, respectively) were more than those in the 6-8 years group (160 cases,41.7%;9 cases,2.3%, respectively; P0.05). And the comorbidity frequencies of the 15-17 years group were significantly higher than those in other age groups (P0.05). Tics disorder in the 12-14 years group (50 cases,20.8%)was more than those in the two age groups of less than 12 years group (for the 6-8 years group, 51 cases,13.4%;for the 9-11 years group , 42 cases,12.5%; P0.05).The comorbidity frequency of learning disorder grew up with age. The comorbidity frequency of the 9-11 years group (106 cases,31.5%) was significantly higher than that of the 6-8 years group (80 cases,20.9%; P0.01); and those of both age groups more than 12 years (for the 12-14 years group, 164 cases,68.0%;for the 15-17 years group, 28 cases,70.0%) were higher than those of the two age groups of less than 12 years (P0.01). ADHD patients without any comorbidities in the two age groups more than 12 years (for the 12-14 years group, 29 cases,12.0%;for the 15-17 years group, 4 cases,10.0%)were less than those in the two age groups of less than 12 years (for the 6-8 years group, 126 cases,32.8%;for the 9-11 years group, 110 cases,32.6%; P0.01). These characteristics maintained in boys.Many comorbid psychiatric disorders increase as the ADHD children become adolescents. The situation is severer in late adolescence. Therefore, ADHD children should accept appropriate treatment as early as possible, and adopt the second degree prevention actively.

To examine the role of dopamine D4 receptor gene (DRD4) in attention deficit hyperactivity disorder (ADHD) with/without disruptive behavior disorder (DBD) by focusing on a-521C/T SNP within the promoter region of this gene.A total of 401 DSM-IV ADHD children (including 284 trios) of Chinese Han descent were genotyped. Chi-square test and the transmission disequilibrium test (TDT) were used to test for associations in ADHD with and without DBD respectively.In the comparison of ADHD with (n=143) and without (n=258) DBD, the -521T allele ( chi(2) = 6.778, P= 0.009, OR= 1.485) and the TT genotype (chi(2) = 6.292,P=0.012,OR=1.729) showed higher frequency in children with ADHD and DBD simultaneously. For family based analysis, T allele of the -521C/T polymorphism was preferentially transmitted to ADHD children with comorbid DBD (n=100, chi(2) = 3.868,P=0.049), whereas no significant distortion was found in the transmission of the tested variant for ADHD without DBD (n=184, chi(2) = 0.223, P=0.637).Our findings suggest that the -521C/T SNP of DRD4 may contribute to the predisposition to ADHD with comorbid DBD. This study supports for the hypothesis that ADHD with comorbid DBD may be influenced by greater genetic effect compared to ADHD alone.