Genome-wide association study in a Chinese population identifies a susceptibility locus for type 2 diabetes at 7q32 near PAX4

AIMS/HYPOTHESIS

Most genetic variants identified for type 2 diabetes have been discovered in European populations. We performed genome-wide association studies (GWAS) in a Chinese population with the aim of identifying novel variants for type 2 diabetes in Asians.

METHODS

We performed a meta-analysis of three GWAS comprising 684 patients with type 2 diabetes and 955 controls of Southern Han Chinese descent. We followed up the top signals in two independent Southern Han Chinese cohorts (totalling 10,383 cases and 6,974 controls), and performed in silico replication in multiple populations.

RESULTS

We identified CDKN2A/B and four novel type 2 diabetes association signals with p < 1 × 10(-5) from the meta-analysis. Thirteen variants within these four loci were followed up in two independent Chinese cohorts, and rs10229583 at 7q32 was found to be associated with type 2 diabetes in a combined analysis of 11,067 cases and 7,929 controls (p meta = 2.6 × 10(-8); OR [95% CI] 1.18 [1.11, 1.25]). In silico replication revealed consistent associations across multiethnic groups, including five East Asian populations (p meta = 2.3 × 10(-10)) and a population of European descent (p = 8.6 × 10(-3)). The rs10229583 risk variant was associated with elevated fasting plasma glucose, impaired beta cell function in controls, and an earlier age at diagnosis for the cases. The novel variant lies within an islet-selective cluster of open regulatory elements. There was significant heterogeneity of effect between Han Chinese and individuals of European descent, Malaysians and Indians.

CONCLUSIONS/INTERPRETATION

Our study identifies rs10229583 near PAX4 as a novel locus for type 2 diabetes in Chinese and other populations and provides new insights into the pathogenesis of type 2 diabetes.

Recombinant disintegrin domain of ADAM15 inhibits the proliferation and migration of Bel-7402 cells

ADAM15 (A Disintegrin And Metalloproteinase 15), a transmembrane protein containing seven domains, interacts with some integrins via its disintegrin domain and overexpresses in many solid tumors. In this study, the effect of the recombinant human disintegrin domain (rhddADAM15) on the proliferation and migration of Bel-7402 cells was evaluated in vitro and in vivo in zebrafish xenografts. rhddADAM15 (4 μM) severely inhibited the proliferation and migration of Bel-7402 cells, inducing a partial G2/S arrest and morphological nucleus changes of apoptosis. Moreover, the activity of caspases 8, 9 and 3 in Bel-7402 cells was increased. In addition, the zebrafish was used as a model for apoptosis-induction and tumor-xenograft. rhddADAM15 (1 pM) inhibited the growth and metastasis of Bel-7402 cell xenografts in zebrafish and a lower concentration (0.1 pM) induced severe apoptosis in the somatic cells of zebrafish. In conclusion, our data identified rhddADAM15 as a potent inhibitor of tumor growth and metastasis, making it a promising tool for use in anticancer treatment.

Open reduction and internal fixation versus external fixation for unstable distal radial fractures: a meta-analysis

PURPOSE

To compare the clinical outcomes of open reduction and internal fixation (ORIF) versus the ones of closed reduction and external fixation (EF) in the treatment of distal radial fractures.

METHODS

We performed a meta-analysis of randomized controlled trials that compared the clinical results of ORIF to EF in the treatment of distal radial fractures. A systemic retrieve from PubMed, EMBASE, OVID and Cochrane Collaboration CENTRAL database resulted in 11 studies with 824 patients. We thus performed data synthesis using RevMan (version 5.1).

RESULTS

Superior statistical differences were observed for DASH scores (at 3, 6 and 12 months follow-up) grip strength (at 3 months follow-up), volar tilt (at 12 months follow-up), flexion and supination (at 3 months follow-up), and extension (at 3 and 6 months follow-up) in ORIF patients group, compared with those in EF group. We also found a significantly higher risk of infection associated with EF. There was no significant difference in the incidence of malunion and median nerve dysfunction.

CONCLUSION

Regarding surgical fixation of unstable distal radius fractures, ORIF yields significantly better subjective outcome (DASH scores) the first year after operation, restoration of anatomic volar tilt, and forearm flexion and extension at the end of the follow-up period. However, EF results in higher incidence of infection compared to ORIF. ORIF is equal to EF for either grip strength, or range of motion of the injured wrist, or incidence of malunion or median nerve dysfunction at the end of the follow-up period.

LEVEL OF EVIDENCE

Level II. Therapeutic study.

High b-value diffusion tensor imaging of the remote white matter and white matter of obstructive unilateral cerebral arterial regions

AIM

To assess diffusion changes in the remote white matter and areas of white matter with cerebral artery obstruction without magnetic resonance imaging (MRI) evidence of brain parenchymal abnormalities using high b-value diffusion tensor imaging (DTI).

MATERIALS AND METHODS

A total of 34 patients with severe unilateral stenosis (≥75%) or occlusion of the middle cerebral artery (MCA) without abnormal brain parenchymal signals at MRI underwent DTI with a b value of 2200 s/mm(2) at 3 T. Fractional anisotropy (FA), apparent diffusion coefficient (ADC), axial diffusivity (eigenvalue λ₁) and radial diffusivity (eigenvalue λ₂₃) were measured at the bilateral corona radiata, anterior and posterior limbs of the internal capsule, cerebral peduncle, and pons.

RESULTS

The mean FA was significantly lower at the ipsilateral corona radiata and anterior and posterior limbs of the internal capsule than at the contralateral corona radiata and anterior and posterior limbs of the internal capsule (p < 0.05). The mean ADC, λ₁ and λ₂₃ were significantly higher at the ipsilateral corona radiata than at the contralateral corona radiata (p < 0.01). The mean λ₂₃ were significantly higher at the ipsilateral anterior and posterior limb of the internal capsule than at the contralateral anterior and posterior limb of the internal capsule (p < 0.05). The mean ADC, λ₁ and λ₂ ₃were not significantly different between the ipsilateral cerebral peduncle and pons.

CONCLUSIONS

High b-value DTI could sensitively reveal diffusion changes in white matter in regions of cerebral artery obstruction without abnormal anisotropy and diffusivity of the remote white matter of patients with severe MCA stenosis or occlusion without MRI evidence of brain parenchymal abnormalities.

A functional MRI study of deception among offenders with antisocial personality disorders

Deceit is a core feature of antisocial personality disorder (ASPD), and the study of deception in ASPD has important implications for identifying the underlying mechanism of ASPD. A great deal of functional neuroimaging literature has described the neural correlates of deception in healthy volunteers, but there have been few imaging studies examining people with ASPD. The neural correlates of lie-telling in ASPD, and which specific brain activities are related to the capacity to lie, are unclear. In this study, 32 offenders who satisfied the Personality Diagnostic Questionaire-4 and PDI-IV (Personality Disorder Interview) criteria for ASPD were divided into three groups based on their capacity for deception, which was evaluated based on the deceitfulness criterion of the PDI-IV ASPD. All offenders underwent functional magnetic resonance imaging (fMRI) while responding to questions in a truthful, inverse, or deceitful manner. We primarily created contrasts in the brain activities between truth-telling and lie-telling, and then computed the Pearson's correlation coefficients between activities contrasts of individual, i.e. BOLD (blood-oxygen-level-dependent) strength during deception minus that during truth-telling, and the capacity for deception. Our results indicated that the bilateral dorsolateral prefrontal cortex extending to the middle frontal gyrus, the left inferior parietal lobule, and the bilateral anterior cingulate gyrus/medial superior frontal gyrus were associated with deception among people with ASPD. As the capacity for deception increased, the contrasted brain activities of the above regions decreased. This study found that truthful and untruthful communications of ASPD subjects can be differentiated in terms of brain BOLD activities, and more importantly, this study is the first to use fMRI to discover that BOLD activities during deception are correlated with the capacity to lie. The latter finding might challenge the diagnostic accuracy of lie detection and may also caution that greater attention should be given to detecting untruths in individuals who are skilled at lying.

Aberrant intrinsic brain activity and cognitive deficit in first-episode treatment-naive patients with schizophrenia

BACKGROUND

Given the important role of the default mode network (DMN) in cognitive function and the well-known neurocognitive deficit in schizophrenia, it is intriguing to examine systematically the relationship between neurocognitive dysfunction and aberrant intrinsic activities, and also functional connectivity, of the DMN in patients with schizophrenia. Method First-episode, treatment-naive patients with schizophrenia (FES) (n = 115) and healthy controls (n = 113) underwent resting-state functional magnetic resonance imaging (fMRI) scans and neurocognitive tests. Intrinsic neural activities evaluated by using the fragment amplitude of low-frequency fluctuations (fALFF) and the resting-state functional connectivity assessed by seed-based correlational analysis were compared between patients and controls. Aberrant intrinsic activities and DMN connectivity in patients were then correlated to neurocognitive performance and clinical symptoms.

RESULTS

Compared to controls, patients with FES showed decreased fALFF in the bilateral medial prefrontal cortex (MPFC) and the orbitofrontal cortex (OFC), and increased fALFF in the bilateral putamen. Increased functional connectivity with the DMN was observed in the left insula and bilateral dorsolateral PFC (DLPFC) in patients with FES. In patients, aberrant fALFF in the bilateral OFC were correlated with cognitive processing speed; fALFF in the left OFC and right putamen were correlated with the clinical factors excited/activation and disorganization; and increased DMN functional connectivity in the left insula was correlated with the clinical factors positive, excited/activation, disorganization and neurocognitive deficit in the domain of sustained attention.

CONCLUSIONS

These associations between neurocognitive dysfunction and aberrant intrinsic activities, and also functional connectivity, of the DMN in patients with schizophrenia may provide important insights into the neural mechanism of the disease.

Isolated cortical vein thrombosis: a widely variable clinicoradiological spectrum

BACKGROUND/AIMS

The aim of this study is to highlight the variable clincoradiological spectrum of isolated cortical vein thrombosis (ICoVT), which seems to remain a challenge to clinicians.

CASES REPORTS

We reported 3 patients with this diagnosis. One presented with only an epileptic seizure, one with worsening headache, seizures, mental disorder, speech disturbance and right-sided weakness, and the other with seizures and fluctuating paralysis in her left-sided limbs. Brain images were manifested with a strand-like abnormal signal, a large hemorrhagic infarction and a continuously enlarged space-occupying massive edema, respectively.

CONCLUSIONS

Neurologic features and brain imaging of ICoVT are highly variable, which might be partly responsible for the underestimation of ICoVT. Clinical diagnosis should probably be evoked more often.

Quadratic scaling of intrinsic Gilbert damping with spin-orbital coupling in L10 FePdPt films: experiments and Ab initio calculations

The dependence of the intrinsic Gilbert damping parameter α(0) on the spin-orbital coupling strength ξ is investigated in L1(0) ordered FePd(1-x) Pt(x) films by time-resolved magneto-optical Kerr effect measurements and spin-dependent ab initio calculations. Continuous tuning of α(0) over more than one order of magnitude is realized by changing the Pt/Pd concentration ratio showing that α(0) is proportional to ξ(2) as changes of other leading parameters are found to be negligible. The perpendicular magnetic anisotropy is shown to have a similar variation trend with x. The present results may facilitate the design and fabrication of new magnetic alloys with large perpendicular magnetic anisotropy and tailored damping properties.

Metabolic syndrome in the prevention of cardiovascular diseases and diabetes--still a matter of debate?

After metabolic syndrome was first introduced to identify persons at greater cardiovascular disease (CVD) risk, it has been associated with an increased risk of CVD and type 2 diabetes (T2D). Obesity has been considered as the fundamental factor in metabolic syndrome and it is thought to be mediated, at least in part by the role of the adipocyte in controlling circulating free fatty acids and the development of insulin resistance. However, the obese population is not perfectly overlapped with the population with metabolic syndrome. Is metabolic syndrome a better predictor than obesity to prevent CVD and T2D? Has metabolic syndrome been considered as a cluster of risk factors or an additional independent risk factor to assess CVD and T2D risk? The debate on the necessity of metabolic syndrome diagnosis seems not to be ended. Various definitions of metabolic syndrome were advocated by different organizations with emphasis on different components, and these definitions have different abilities to predict CVD and T2D among different populations because of fundamental philosophical differences. In the definitions of metabolic syndrome, only the cutoffs of each component were presented but rather continuous values or the degree of the severity of the syndrome with multiple cutoffs. Moreover, metabolic syndrome did not incorporate all the risk factors as known for CVD and T2D, such as physical activity. Future prospective studies with the measurement of sophisticated metabolic markers and of abdominal visceral and subcutaneous adiposity are needed to examine if the metabolic syndrome is a good CVD and T2D risk predictor over obesity and other risk factors. In practice, prevention action should be taken at the stage of obesity and providers need to pay attention to any components in the definition of metabolic syndrome even if the number of positive components has not achieved three or more.

Otoprotective effects of erythropoietin on Cdh23erl/erl mice

The Cdh23(erl/erl) mice are a novel mouse model for DFNB12 and are characterized by progressive hearing loss. In this study, erythropoietin (EPO) was given to the Cdh23(erl/erl) mice by intraperitoneal injection every other day from P7 for 7 weeks. Phosphate-buffered saline-treated or untreated Cdh23(erl/erl) mice were used as controls. Auditory-evoked brainstem response (ABR) thresholds and distortion product oto-acoustic emission (DPOAE) were measured in the mouse groups at the age of 4, 6 and 8 weeks. The results show that EPO can significantly decrease the ABR thresholds in the Cdh23(erl/erl) mice as compared with those of the untreated mice at stimulus frequencies of click, 8-, 16- and 32-kHz at three time points. Meanwhile, DPOAE amplitudes in the EPO-treated Cdh23(erl/erl) mouse group were significantly higher than those of the untreated groups at f2 frequency of 15383 Hz at the three time points. Furthermore, the mean percentage of outer hair cell loss at middle through basal turns of cochleae was significantly lower in EPO-treated Cdh23(erl/erl) mice than in the untreated mice (P<0.05). This is the first report that EPO acts as an otoprotectant in a DFNB12 mouse model with progressive hearing loss.

Exome sequencing-driven discovery of coding polymorphisms associated with common metabolic phenotypes

AIMS/HYPOTHESIS

Human complex metabolic traits are in part regulated by genetic determinants. Here we applied exome sequencing to identify novel associations of coding polymorphisms at minor allele frequencies (MAFs) >1% with common metabolic phenotypes.

METHODS

The study comprised three stages. We performed medium-depth (8×) whole exome sequencing in 1,000 cases with type 2 diabetes, BMI >27.5 kg/m(2) and hypertension and in 1,000 controls (stage 1). We selected 16,192 polymorphisms nominally associated (p < 0.05) with case-control status, from four selected annotation categories or from loci reported to associate with metabolic traits. These variants were genotyped in 15,989 Danes to search for association with 12 metabolic phenotypes (stage 2). In stage 3, polymorphisms showing potential associations were genotyped in a further 63,896 Europeans.

RESULTS

Exome sequencing identified 70,182 polymorphisms with MAF >1%. In stage 2 we identified 51 potential associations with one or more of eight metabolic phenotypes covered by 45 unique polymorphisms. In meta-analyses of stage 2 and stage 3 results, we demonstrated robust associations for coding polymorphisms in CD300LG (fasting HDL-cholesterol: MAF 3.5%, p = 8.5 × 10(-14)), COBLL1 (type 2 diabetes: MAF 12.5%, OR 0.88, p = 1.2 × 10(-11)) and MACF1 (type 2 diabetes: MAF 23.4%, OR 1.10, p = 8.2 × 10(-10)).

CONCLUSIONS/INTERPRETATION

We applied exome sequencing as a basis for finding genetic determinants of metabolic traits and show the existence of low-frequency and common coding polymorphisms with impact on common metabolic traits. Based on our study, coding polymorphisms with MAF above 1% do not seem to have particularly high effect sizes on the measured metabolic traits.

Reference charts and equations of fetal biometry for normal singleton pregnant women in Shaanxi, China

OBJECTIVE

To construct reference charts and equations of fetal biometry for singleton pregnant women in Shaanxi, China.

MATERIALS AND METHODS

This was a cross-sectional study involving 6,832 singleton pregnant women. One set of fetal ultrasonographic measurement data between the 16th to 41st gestational weeks (GW) was randomly selected from each pregnant woman, and biparietal diameter (BPD), abdominal circumference (AC), and femur length (FL) were recorded. Mean and standard deviation (SD) of BPD, AC, and FL were fitted by polynomial. Centile = Mean + Z(alpha) x SD was used to calculate centiles. Differences in the 50th centile of BPD, AC, and FL between Hong Kong, Korean, Italian and Shaanxi fetuses were compared.

RESULTS

Mean of BPD, AC, and FL were well-fitted by quadratic polynomial, SD of BPD, AC and FL were fitted by linear regression. Equations for estimating mean and SD for BPD, AC, and FL from GW were obtained. Centiles for BPD,AC, and FL were calculated. From the 21st GW, the differences in BPD,AC, and FL between Hong Kong, Korean, Italian, and Shaanxi fetuses became larger.

CONCLUSION

Fetal biometry reference charts and equations for estimating fetal size and GW could be used in obstetrics practice and research in Shaanxi, China.

Genetic variants of LPIN1 indicate an association with Type 2 diabetes mellitus in a Chinese population

AIMS

Metabolic disorders are independent risk factors for the development of Type 2 diabetes. The aim of the study is to test the association of LPIN1 variants with Type 2 diabetes and clinical characteristics in large samples of the Chinese population.

METHODS

In the first stage, 15 single nucleotide polymorphisms within the LPIN1 region were selected and genotyped in 3700 Chinese Han participants. In the second stage, the single nucleotide polymorphisms showing significant association or trends towards association were genotyped in an additional 3122 samples for replication. Meta-analyses and genotype-phenotype association studies were performed after combining the data from the two stages.

RESULTS

In the first stage, we detected that rs16857876 was significantly associated with Type 2 diabetes with an odds ratio of 0.806 (95% CI 0.677-0.958, P = 0.015), while rs11695610 showed a trend with Type 2 diabetes (odds ratio 0.846, 95% CI 0.709-1.009, P = 0.062). In the second stage, a similar effect of rs11695610 on Type 2 diabetes was observed (odds ratio 0.849, 95% CI 0.700-1.030, P = 0.096). The meta-analyses combining the information from the two stages showed a significant effect of rs11695610 on Type 2 diabetes with an odds ratio of 0.847 (95% CI 0.744-0.965, P = 0.012). Finally, the phenotype-genotype association analyses showed that rs11695610 was associated with 2-h plasma glucose (P = 0.040) and triglyceride levels (P = 0.034).

CONCLUSIONS

Our data implied that common single nucleotide polymorphisms within the LPIN1 region were associated with Type 2 diabetes and metabolic traits in the Chinese population.

Analysis of genetic diversity among wild bermudagrass germplasm from southwest China using SSR markers

Fifty-five wild accessions of bermudagrass (Cynodon dactylon) were collected from southwest China (Sichuan, Chongqing, Yunnan, Guizhou, and Tibet), and their genetic diversity was analyzed using simple sequence repeat markers. A total of 267 polymorphic bands were detected with 18 primer combinations. The genetic similarity among the accessions ranged from 0.688 to 0.894 with an average of 0.797. All 55 wild accessions were clustered into 7 eco-geographic groups. Our data showed that the dendrogram was almost in accordance with geographic distribution, and accessions from the same collection sites tended to be clustered into the same group. A genetic differentiation analysis revealed that the percentage of genetic variance was 70.07 and 29.93% within and among groups, respectively. Finally, we discuss the implications of these results for C. dactylon in southwest China.

Leukemoid reaction in malignant bone tumor patients - a retrospective, single-institution study

BACKGROUND

To the Authors' knowledge, the literature regarding leukemoid reaction in patients with malignant bone tumor is sparse, and most of patients with leukemoid reaction have poor prognosis.

AIM

To study the leukemoid reaction in malignant bone tumor patients.

MATERIALS AND METHODS

A total of 105 consecutive malignant bone tumor patients with a white blood cell count > 50,000/microL were retrospectively identified over a 4-years period (2007-2010). Those patients without a secondary cause of their leukocytosis were defined as having a paraneoplastic leukemoid reaction.

RESULTS

Three etiologies of the leukocytosis were found in those 105 patients: the major one was paraneoplastic leukemoid reaction which accounted for 56%; the second one was hematopoietic growth factors defect accounting for 30%; 14% patients were caused by infection and Tumor bone marrow involvement. The patients diagnosed with a paraneoplastic leukemoid reaction typically had neutrophil predominance (94.8%) and radiographic evidence of metastatic diseases (78%). They were clinically stable, but had a poor prognosis. 95% either died or were discharged to hospice within 12 weeks of their initial extreme leukocyte count. Both of the 2 (2%) patients who survived over 12 weeks received effective antineoplastic therapy.

CONCLUSIONS

Patients with typical paraneoplastic leukemoid reaction were clinically stable despite having large tumor burdens. However, clinical outcomes were poor unless receiving an effective antineoplastic treatment.