27-Hydroxycholesterol contributes to hypercholesterolemia-associated aggravation of apical periodontitis in ovariectomized rats and raloxifene counteracts its action.

AIM: The influence of hypercholesterolemia on the development of apical periodontitis (AP) is inconclusive. Recent studies revealed that cholesterol metabolite 27-hydoxycholesterol (27HC) can affect cellular responses to bacterial infections and oestrogen status and raloxifene may influence its action. Herein, we aimed to examine the impact of 27HC on production of inflammatory mediators by macrophages and the regulatory function of raloxifene. The contribution of 27HC to AP development and the therapeutic effect of raloxifene were evaluated in a rat model. METHODS: Murine macrophages J774 cells were used. The expression of inducible nitric oxide synthase (iNOS) was examined by Western blot. The concentrations of C-C motif chemokine ligand (CCL) 2 and 27HC were assessed by enzyme-linked immunosorbent assay. Colorimetric assay was used to evaluate cholesterol levels. Experimental AP was induced in ovariectomized (OVX) or un-operated rats receiving high-fat/high-cholesterol diet (HFHCD) or normal diet (ND). Micro-computed tomography and immunohistochemistry were employed to evaluate disease severity and the therapeutic effect of raloxifene. RESULTS: Cholesterol enhanced 27HC production in macrophages. 27HC induced iNOS and CCL2 synthesis by macrophages and estradiol suppressed the responses. In our animal model of AP, HFHCD plus OVX significantly augmented serum and lesion tissue levels of 27HC (p < .05 versus the ND group). Lesion size, infiltration of CD68+ cells, and iNOS+ monocytes were increased in parallel with 27HC accumulation. Raloxifene inhibited pro-inflammatory effects of 27HC on macrophages and suppressed AP progression in HFHCD/OVX rats (p < .05 versus the vehicle control group). CONCLUSIONS: Our results suggested that 27HC contributes to AP aggravation associated with hypercholesterolemia. Oestrogen deficiency may both enhance 27HC production and exacerbate its downstream action.

Tunneled island pedicle flap reconstruction for upper lateral cutaneous lip defects.

BACKGROUND: Esthetic upper lateral cutaneous lip reconstruction preserves the apical triangle, nasolabial fold symmetry, and free margin position. The tunneled island pedicle flap (IPF) is a novel single-stage reconstruction to achieve these goals. OBJECTIVES: Describe the technique and patient and surgeon-reported outcomes for the tunneled IPF reconstruction of upper lateral cutaneous lip defects. METHODS: Retrospective chart review of consecutive tunneled IPF reconstruction following Mohs micrographic surgery (MMS) at a tertiary care center between 2014 and 2020. Patients rated their scars using the validated Patient Scar Assessment Scale (PSAS), and independent surgeons rated scars using the validated Observer Scar Assessment Scale (OSAS). Descriptive statistics were generated for patient demographics and tumor defect characteristics. RESULTS: Twenty upper lateral cutaneous lip defects were repaired with the tunneled IPF. Surgeons rated scars with a composite OSAS score of 11.83 ± 4.29 (mean, SD) [scale of 5 (normal skin) to 50 (worst scar imaginable)] and an overall scar score of 2.81 ± 1.11 [scale of 1 (normal skin) to 10 (worst scar imaginable)]. Patients rated their scars with a composite PSAS score of 10 ± 5.39 [scale of 6 (best possible score) to 60 (worst)] and with an overall score of 2.2 ± 1.78 [scale of 1 (normal skin) and 10 (very different from normal skin)]. One flap was surgically revised for pincushioning, but none experienced necrosis, hematoma, or infection. CONCLUSIONS: The tunneled IPF is a single-stage reconstruction for upper lateral cutaneous lip defects with favorable scar ratings by patients and observers.

Blockade of fatty acid signalling inhibits lipopolysaccharide-induced macrophage recruitment and progression of apical periodontitis.

AIM: To examine the role of palmitic acid in lipopolysaccharide (LPS)-stimulated chemotaxis of macrophages and the potential contribution of saturated fatty acid in signalling during the pathogenesis of apical periodontitis. METHODOLOGY: J774, a mouse macrophage cell line, was used in the experiments. After treatment with LPS, proteolytic maturation of sterol regulatory element-binding protein-1c (SREBP-1c) and expression of fatty acid synthase (FASN) were examined by Western analysis. Levels of palmitic acid were measured by reverse phase-high performance liquid chromatography-mass spectrometry. Knockdown of SREBP-1c and FASN was accomplished by small interfering RNA technology. Secretion of CC-chemokine ligand 2 (CCL2) and cellular chemotaxis were assessed by enzyme-linked immunosorbent assay and transwell migration assay, respectively. Sulfo-N-succinimidyl oleate (SSO) treatment was used to inhibit fatty acid signalling in vitro and also in a rat model of apical periodontitis. All data were first subjected to Levene's test. In vitro data were then analysed using ANOVA followed by Tukey's multiple comparison test. Data from animal experiments were analysed by independent t-tests. The significant level was set at 0.05. RESULTS: LPS stimulated proteolytic maturation of SREBP-1c and FASN expression in macrophages and significantly enhanced palmitic acid synthesis (P < 0.05). Knockdown of SREBP-1c attenuated LPS-enhanced FASN expression. Knockdown of FASN significantly suppressed LPS-enhanced palmitic acid synthesis (P < 0.05). LPS and exogenous palmitic acid significantly enhanced CCL2 secretion and macrophage chemotaxis (all P < 0.05). Inhibition of FASN expression significantly alleviated LPS-augmented CCL2 secretion (P < 0.05). SSO significantly suppressed CCL2 secretion and macrophage chemotaxis augmented by LPS and palmitic acid (all P < 0.05). In a rat model of induced apical periodontitis, SSO treatment significantly attenuated progression of apical periodontitis and macrophage recruitment (all P < 0.05). CONCLUSIONS: LPS/SREBP-1c/FASN/palmitic acid signalling contributed to tissue destruction caused by bacterial infection. Modulation of lipid metabolism and signalling may be helpful for the management of apical periodontitis.

Circular RNA circ_0067934 functions as an oncogene in glioma by targeting CSF1.

Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "Circular RNA circ_0067934 functions as an oncogene in glioma by targeting CSF1, by X.-L. Cui, X.-D. Wang, S.-K. Lin, C.-M. Miao, M. Wu, J.-G. Wei, published in Eur Rev Med Pharmacol Sci 2019; 23 (19): 8449-8455-DOI: 10.26355/eurrev_201910_19157-PMID: 31646575" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/19157.

Circular RNA circ_0067934 functions as an oncogene in glioma by targeting CSF1.

OBJECTIVE: The importance of circular RNAs in malignant tumors increases the attention of researchers. The role of circ_0067934 in glioma remains unclear. Our study aims to uncover how circ_0067934 functions in glioma development. PATIENTS AND METHODS: Real Time-quantitative Polymerase Chain Reaction (RT-qPCR) was utilized to determine the level of circ_0067934 in glioma tissues. Circ_0067934 was knocked down in glioma cells. Cell migrated and invaded ability was detected through functional assay in vitro and in vivo. Further mechanism assays were performed to explore the potential targets of circ_0067934. RESULTS: The circ_0067934 was highly expressed in glioma tissues compared with adjacent samples. The expression of circ_0067934 was upregulated in glioma cell lines. The cell migrated and invaded ability of glioma cells was inhibited after circ_0067934 was knocked down. Besides, CSF1 expression was decreased via knockdown of circ_0067934. Furthermore, tumor metastasis was inhibited after circ_0067934 was knocked down in nude mice. CONCLUSIONS: The circ_0067934 could suppress cell migration and invasion of glioma by upregulating CSF1.

Simvastatin alleviates bone resorption in apical periodontitis possibly by inhibition of mitophagy-related osteoblast apoptosis.

AIM: To assess the connection between mitophagy and hypoxia-induced apoptosis in osteoblasts and whether simvastatin alleviates bone resorption in apical periodontitis through modulation of mitophagy-related apoptosis. METHODOLOGY: Hypoxia-induced generation of reactive oxygen species in mitochondria and changes in mitochondrial membrane potential were evaluated, respectively, by MitoSOX and JC-1 fluorescence dye signalling. Accumulation of mitophagy markers PTEN-induced putative kinase 1 (PINK1) and Parkin in mitochondria was examined by Western blotting and immunofluorescence microscopy. Osteoblast apoptosis was assessed by Western analysis of cleaved-poly (adenosine diphosphate ribose) polymerase (PARP). In a rat model of induced apical periodontitis, the therapeutic effect of simvastatin and its action on osteoblast mitophagy and apoptosis were examined. anova, Fisher's and Student's t-test were used for data analysis. RESULTS: Hypoxia-induced mitochondrial dysfunction and stimulated mitophagy in osteoblasts. Hypoxia also provoked apoptosis in osteoblasts and inhibition of mitophagy decreased hypoxia-augmented apoptotic activity. Simvastatin alleviated hypoxia-induced mitochondrial dysfunction, mitophagy and apoptosis. The protective action of simvastatin against apoptosis was related to its antimitophagy activity. Experiments in the rat model of induced apical periodontitis supported the laboratory findings. Simvastatin treatment mitigated periapical bone loss and reduced the activities of apoptosis and mitophagy in regional osteoblasts. CONCLUSIONS: The results suggest that modulation of osteoblast mitophagy may help diminish bone loss associated with inflammation and has potential as an auxiliary therapy for apical periodontitis.

Correction to: CCN2 inhibits lung cancer metastasis through promoting DAPK-dependent anoikis and inducing EGFR degradation.

Following publication of their article "CCN2 inhibits lung cancer metastasis through promoting DAPK-dependent anoikis and inducing EGFR degradation", the authors reported an error in Fig.6b. α-Tubulin image of rCCN2 treatment  (upper panel in CL1-5) only showed eight lanes, when there should be nine.

Sirtuin 6 attenuates periapical lesion propagation by modulating hypoxia-induced chemokine (C-C motif) ligand 2 production in osteoblasts.

AIM: To investigate the attenuating effect of sirtuin 6 (SIRT6) on hypoxia-induced production of chemokine (C-C motif) ligand 2 (CCL2) by osteoblasts and the relevance of this action on the pathogenesis of periapical lesions. METHODOLOGY: Sirtuin 6 was overexpressed in MC3T3-E1 murine osteoblasts by lentivirus-mediated gene transfer. The relationship between the antiglycolytic/antioxidative activities of SIRT6 and its effect on hypoxia-induced CCL2 production were examined. Pathogenetic relevance of the actions of SIRT6 was assessed in a rat model of induced apical periodontitis. The data were analysed statistically using Student's t-test or one-way analysis of variance (anova) and then a Tukey's multiple comparison test. RESULTS: In cultured murine osteoblasts, 24-h hypoxic treatment significantly enhanced the generation of reactive oxygen species (P = 0.003), expression of lactate dehydrogenase A (LDHA) and production of lactate (P = 0.007). A reciprocal effect between hypoxia-induced redox imbalance and hypoxia-enhanced glycolysis was noted which in turn augmented the secretion of CCL2. Through its antiglycolytic and antioxidative effects, SIRT6 blocked the vicious cycle to suppress CCL2 production. In normal periapical tissues of rats, strong expression of SIRT6 and low levels of LDHA and 8-OHdG (a marker of oxidative DNA damage) were found in osteoblasts. In induced apical periodontitis, osteoblastic expression of SIRT6 was significantly suppressed (P = 0.001) which was associated with significantly elevated levels of LDHA (P = 0.003) and 8-OHdG (P = 0.004) and significantly enhanced recruitment of macrophages (P = 0.004). CONCLUSIONS: Sirtuin 6 has a therapeutic effect on periapical lesions through suppression of CCL2 synthesis. The anti-inflammatory action of SIRT6 is closely related to its regulatory activities in cellular metabolism and redox homoeostasis.

Faraday instability-based micro droplet ejection for inhalation drug delivery.

We report here the technology and the underlying science of a new device for inhalation (pulmonary) drug delivery which is capable of fulfilling needs unmet by current commercial devices. The core of the new device is a centimeter-size clog-free silicon-based ultrasonic nozzle with multiple Fourier horns in resonance at megahertz (MHz) frequency. The dramatic resonance effect among the multiple horns and high growth rate of the MHz Faraday waves excited on a medicinal liquid layer together facilitate ejection of monodisperse droplets of desirable size range (2-5 µm) at low electrical drive power (<1.0 W). The small nozzle requiring low drive power has enabled realization of a pocket-size (8.6 × 5.6 × 1.5 cm3) ultrasonic nebulizer. A variety of common pulmonary drugs have been nebulized using the pocket-size unit with desirable aerosol sizes and output rate. These results clearly provide proof-of-principle for the new device and confirm its potential for commercialization.

Identification of novel loci for bipolar I disorder in a multi-stage genome-wide association study.

OBJECTIVE: Identification of genetic variants that influence bipolar I disorder (BPD-I) through genome-wide association (GWA) studies is limited in Asian populations. The current study aimed to identify novel common variants for BPD-I in an ethnically homogeneous Taiwanese sample using a multi-stage GWA study design. METHOD: At the discovery stage, 200 BPD-I patients and 200 controls that combined to form 16 pools were genotyped with 1 million markers. Utilizing a newly developed rank-based method, top-ranked markers were selected. After validation with individual genotyping, a fine-mapping association study was conducted to identify associated loci using 240 patients and 240 controls. At the last stage, independent samples were collected (351 cases and 341 controls) for replication. RESULTS: Among the top-ranked markers from the discovery stage, eight genes and 15 individual SNPs were evaluated in the fine-mapping stage. At this stage, rs7619173, which is not in a gene coding region, showed the most significant association (P = 2 ∗ 10(-5)) with BPD-I. Four genes had empirical P-values<0.05, including KCNH7 (P = 0.0047), MYST4 (P = 0.0047), NRXN3 (P = 0.0095), and SEMA3D (P = 0.037). For markers genotyped in replication samples, rs7619173 exhibited a significant association (P(combined) = 2 ∗ 10(-4)) after multiple testing correction, while markers rs11001178 (MYST4) and rs2217887 (NRXN3) showed weak associations (P(combined) = 0.02) with BPD-I. CONCLUSION: A multi-stage GWA design has the potential to uncover the underlying pathogenesis of a complex trait. Findings in the present study highlight three loci that warrant further investigation for bipolar.

HLA-DPB1 and anti-HBs titer kinetics in hepatitis B booster recipients who completed primary hepatitis B vaccination during infancy.

Previously we reported significant associations of the human leukocyte antigen (HLA)-DPB1 05:01 with memory against hepatitis B (HB) vaccination. However, the effects of HLA-DPB1 on antibodies to hepatitis B surface antigen (anti-HBs) kinetics were not explored. We followed up a cohort of 1974 HB booster recipients and quantified their 1-month and 1-year post-booster anti-HBs titers. A total of 681 subjects were randomly selected and typed for HLA-DPB1. We found that male subjects, undetectable pre-booster titers, and 05:01 homozygotes led to significantly lower post-booster anti-HBs titers. The geometric means (95% confidence interval (CI)) of 1-month post-booster anti-HBs titers were 4.68 (2.69-8.12), 23.01 (14.96-35.40) and 50.06 (27.20-92.13) mIU ml(-1) for subjects carrying two, one and no HLA-DPB1 05:01 allele. The corresponding figures for 1-year post-booster anti-HBs titers were 1.26 (0.73-2.18), 4.72 (3.08-7.25) and 7.32 (3.75-13.56) mIU ml(-1). There were significant associations of post-booster anti-HBs titers with the number of HLA-DPB1 risk and protective alleles. Among booster responders, anti-HBs decay rates were significantly reduced in subjects who had detectable pre-booster anti-HBs titers and the HLA-DPB1 05:01 allele. Our results indicated that HLA-DPB1 influences the kinetics of anti-HBs. The long-term memory against hepatitis B surface antigen (HBsAg) and the residual serum titers of anti-HBs after HB vaccination may be influenced by different mechanisms as evidenced by their inverse trend of associations with the 05:01 allele.

CCN2 inhibits lung cancer metastasis through promoting DAPK-dependent anoikis and inducing EGFR degradation.

CCN family protein 2 (CCN2), also known as connective tissue growth factor, is a secreting protein that modulates multiple cellular events. We previously demonstrated the metastasis-suppressive effect of CCN2 in lung cancer cells. In this study, we investigate the role of CCN2 in anoikis, a form of programmed cell death that is critical in suppressing cancer metastasis. CCN2 binds to the epidermal growth factor receptor (EGFR) and triggers ubiquitination by inhibiting the formation of the ß-pix/Cbl complex, resulting in the degradation of EGFR. Binding of CCN2 to EGFR suppresses the phosphorylation of c-Src and extracellular signal-regulated kinase but increases the expression of death-associated protein kinase, which leads to anoikis. Overall, our findings provide evidence validating the use of CCN2 as an anti-metastatic therapy in lung cancer patients, and prospect a potential therapeutic synergy between CCN2 and the anti-EGFR antibody for the treatment of lung cancer.

Connective tissue growth factor modulates oral squamous cell carcinoma invasion by activating a miR-504/FOXP1 signalling.

Connective tissue growth factor (CTGF) is a multi-functional secreted protein, and it has been shown either to promote or suppress tumor progression among different kinds of cancers. Here, we investigated the role of CTGF in oral squamous cell carcinoma (OSCC) invasion and metastasis. In five OSCC cell lines, endogenous CTGF negatively correlated with invasiveness. Exogenous CTGF protein or forced expression of CTGF gene in the oral cancer cell line SAS significantly decreased their invasive and migratory abilities. MicroRNA (miRNA) microarray analysis was performed in CTGF-overexpressed SAS cells (SAS/CTGF-M3) versus control cells to investigate the mechanism of CTGF-mediated inhibition of OSCC invasion. Among the miRNAs regulated by CTGF, miR-504 and miR-346 were the top two miRNAs downregulated in CTGF transfectants, and the result was confirmed by quantitative reverse transcriptase-PCR. Ectopic miR-504 increased migration and invasion in SAS/CTGF-M3, however, miR-346 did not have such impact on migration/invasion. Furthermore, we identified FOXP1, a member of forkhead transcription factors, as a target gene that takes part in the miR-504-induced cellular invasion. Knockdown of FOXP1 increased invasiveness in SAS/CTGF-M3, confirming the signal axis of CTGF/miR-504/FOXP1 in OSCC. Animal experiments showed that SAS/CTGF-M3-formed orthotopic tumors were associated with a lesser invasive phenotype than control cells. Expression of miR-504 in SAS/CTGF-M3 increased lymph node metastasis, and co-expression of FOXP1 in miR-504-transfected SAS/CTGF-M3 alleviated miR-504-induced metastasis. In OSCC samples, high CTGF was associated with a lower clinical stage and a better outcome. A reverse correlation between CTGF and miR-504, miR-504 and FOXP1, and a positive correlation between CTGF and FOXP1 were shown. Our study discovers a novel signal pathway involving the regulation of miRNA machinery by a secreted cytokine, which will be beneficial for developing therapeutic strategy against advanced OSCC.

In situ preparation of an ultra-thin nanomask on a silicon wafer.

Porous nanomasks have been prepared in situ on an insulating silicon wafer by anodization of an aluminum film grown on it. Ultra-thin nanomasks, around 50 nm thick, were fabricated by utilizing a stop signal, a vivid color appearing at the air-electrolyte interface, and the process involved showed excellent repeatability. Finally, 2D nanoscale p-n junction arrays were fabricated on a silicon on insulator (SOI) wafer using the ultra-thin nanomasks prepared. The experimental results are in good agreement with the simulated results on the characteristics of the anodization process involved.

Nitric oxide promotes the progression of periapical lesion via inducing macrophage and osteoblast apoptosis.

This study aimed to elucidate the modulation by nitric oxide (NO) of the apoptosis of macrophages and osteoblasts, the essential cellular components in the development of periapical lesions. Lipopolysaccharide (LPS) induced prominent nitrite synthesis in J774 mouse macrophage cell lines. Exposure to LPS induced obvious apoptosis in J774 cells, whereas transient transfection with murine inducible nitric oxide synthase (iNOS), small interfering RNA (siRNA) diminished this effect. Tumor necrosis factor-alpha (TNF-alpha) and S-nitroso-N-acetyl-DL-penicillamine (SNAP) (a NO donor) triggered apoptosis in UMR-106 rat osteoblastic cell lines and a synergistic effect was noted when TNF-alpha and SNAP were added to the medium together. Administration of siRNAs for c-Fos and c-Jun: components of activator protein-1 (AP-1) and transforming growth factor-beta1 attenuated the combined effect markedly. Terminal deoxynucleotidyl transferase-mediated nick end-labeling (TUNEL) stain in a rat model of induced periapical lesion showed positive apoptotic signals in macrophages and osteoblasts. Administration of N(G)-monomethyl-l-arginine markedly diminished the extent of bone loss and the amounts of apoptotic macrophages and osteoblasts. In conclusion, NO mediates LPS-stimulated apoptosis of macrophages. It also induces osteoblast apoptosis and augments the pro-apoptotic effect of cytokines. Inhibition of NO synthesis in vivo attenuates apoptosis and the size of periapical lesions. Taken together, these results suggest that NO may promote the progression of periapical lesion by inducing the apoptosis of macrophages and osteoblasts.

Clinical relevance of musical murmurs in color-coded carotid and transcranial duplex sonographies.

BACKGROUND AND PURPOSE: Musical murmurs (MMs), sometimes called seagull cry, goose cry, honks, or cooing murmur, are murmurs with a single frequency that sounds like a musical tone. Doppler detections usually show mirror-image parallel strings or bands of low to moderate frequency. Musical murmurs are mostly described in cardiac murmurs and have seldom been mentioned in cerebrovascular disease. METHODS: A retrospective review of 12,000 patients from our neurosonographic data base of the past 7 years was conducted to find patients who had MMs during color-coded carotid and transcranial duplex sonographies. RESULTS: Sixty-six musical murmurs were found in 60 patients (0.5% of all studied patients). There were 44 men and 16 women with a mean age of 63.8 years. Musical murmurs may occur with or without simultaneous turbulent flows, or very close to a high-intensity frequency (with systolic spindles) turbulent flow. Musical murmurs are detected more frequently in intracranial vessels (94%) than in extracranial cervical arteries. The pathologic changes corresponding to the area of MMs were high-grade stenosis of the arteries (58 MMs), small arteries serving as collateral circulation (5 MMs), carotid cavernous sinus fistulas (2 MMs), and Moyamoya disease (1 MM). Fifty (88%) of 57 patients with stenotic arterial lesions had histories of cerebral infarction or transient ischemic attack, and 64% of the cerebrovascular events occurred on the side appropriate to the MMs. CONCLUSIONS: The presence of MMs in color-coded carotid duplex and transcranial color-coded duplex sonography imply severe underlying vascular diseases that require prompt treatment. Further cerebral angiographic study is warranted to clarify the underlying pathology in patients with MMs.

Pre-morbid characteristics and co-morbidity of methamphetamine users with and without psychosis.

BACKGROUND: The long-term use of methamphetamine (MAMP) can result in psychosis but it is not clear why some individuals develop psychotic symptoms, while others use MAMP regularly over long periods and remain unscathed. We set out to characterize MAMP users and to examine the relationship of pre-morbid personality, pre-morbid social function and other psychiatric disorders to MAMP psychosis. METHOD: Four hundred and forty-five amphetamine users were recruited from a psychiatric hospital and a detention centre in Taipei, and were assessed with the Diagnostic Interview for Genetic Studies (DIGS). Their parents were interviewed with the Premorbid Schizoid and Schizotypal Traits (PSST) and the Premorbid Social Adjustment (PSA) schedules. Pre-morbid characteristics and psychiatric co-morbidity were compared between the MAMP users with a lifetime diagnosis of MAMP psychosis and those without. RESULTS: The MAMP users with psychosis presented a clinical picture which mimicked the positive symptoms of schizophrenia: 85% had auditory hallucinations; 71% persecutory delusions; 63% delusions of reference. Compared with their non-psychotic counterparts, these MAMP users were younger at first MAMP use, used larger amounts of MAMP, had a significantly higher mean PSST score, and higher rates of major depressive disorder, alcohol dependence and antisocial personality disorder. CONCLUSIONS: Earlier and larger use of MAMP was associated with increased risk of psychosis. Our data are also compatible with the view that pre-morbid schizoid/schizotypal personality predisposes MAMP users to develop psychosis, and that the greater the personality vulnerability, the longer the psychosis will persist.

Gender-specific contribution of the GABA(A) subunit genes on 5q33 in methamphetamine use disorder.

Family and twins studies have suggested that genetic factors are involved in the development of substance use disorders. Several unrelated case/control association studies have reported associations of the GABA(A) subunit genes on 5q33 with the development of alcohol dependence. We hypothesized that these particular GABA(A) subunit genes also contribute to the development of methamphetamine use disorder. To test our hypothesis, we recruited cases using a series of questionnaires. Among the polymorphic SNPs, significant differences between cases and controls were identified in the female sample in the rs2279020 of the GABA(A)alpha1 subunit gene, and the novel SNP rs4480617 in the GABA(A)gamma2 subunit gene. No associations were found in the male sample. Further haplotype analysis identified several marker blocks significantly associated with methamphetamine use disorder in females; each block consists of the rs4480617. Our study provides preliminary evidence that the GABA(A) subunit genes on 5q33 may preferentially contribute to methamphetamine use disorder in females.

The dopamine transporter gene is associated with attention deficit hyperactivity disorder in a Taiwanese sample.

Genetic variation of the dopamine transporter gene (DAT1) is of particular interest in the study of attention-deficit hyperactivity disorder (ADHD), since stimulant drugs interact directly with the transporter protein. Association between ADHD and the 10-repeat allele of a 40-bp VNTR polymorphism that lies within the 3'-UTR of DAT1 was first reported in 1995, a finding that has been replicated in at least six independent samples from Caucasian populations. We analysed the DAT1 polymorphism in a sample of 110 Taiwanese probands with a DSM-IV diagnosis of ADHD and found evidence of increased transmission of the 10-repeat allele using TRANSMIT (chi(2)=10.8, 1 d.f., p=0.001, OR=2.9, 95% CI 1.4-6.3). These data give rise to a similar odds ratio to that observed in Caucasian poplulations despite a far higher frequency of the risk allele in this Taiwanese population; 82.3% in the un-transmitted parental alleles and 94.5% in the ADHD probands. These data support the role of DAT1 in ADHD susceptibility among Asian populations.