Sleep duration and timing in relation to osteoporosis in an elderly Chinese population: a cross-sectional analysis in the Dongfeng-Tongji cohort study

This population-based cross-sectional study in an older Chinese population shows a link between sleep duration, sleep timing, and osteoporosis risk, suggesting that sleep may have a role in osteoporosis development. These findings may help to identify contributing mechanisms and provide new opportunities for sleep-focused interventions to prevent osteoporosis.

INTRODUCTION

Accumulated evidence suggests that sleep pattern disruption may lead to alterations in physiology, potentially triggering the development of osteoporosis. The present study sought to examine whether sleep duration or sleep timing is associated with osteoporosis.

METHODS

A total of 31,769 participants (aged 45-86 years) were recruited from the Dongfeng-Tongji cohort study. All participants completed questionnaires and medical examinations and provided blood samples. The presence of osteoporosis was determined using calcaneal quantitative ultrasonography. Logistic regression models were used to evaluate the association of sleep duration and timing with osteoporosis, after adjusting for potential confounders.

RESULTS

The prevalence of osteoporosis was 14.2 % in men and 23.9 % in women. After controlling for potential confounders, the adjusted odds ratio (OR) [95 % confidence interval (CI)] for osteoporosis comparing sleep duration of 9 h or longer with the reference (7-8 h) was 1.40 (1.22-1.62) in men and 1.20 (1.07-1.33) in women. Men with early sleep timing (going to sleep before 21:00 h) were more likely to have osteoporosis (OR, 1.43; 95 % CI, 1.16-1.78) than those with normal sleep timing (going to sleep between 21:00 and 23:00 h). In the interaction analysis, participants with long sleep duration and early sleep timing had the highest risk of osteoporosis both in men (OR, 1.79; 95 % CI, 1.48-2.16) and women (OR, 1.41; 95 % CI, 1.19-1.66).

CONCLUSIONS

Long sleep duration (≥9 h) and early sleep timing were independently and interactively associated with an increased risk of osteoporosis in this older Chinese population.

Validation of the Mandarin Chinese version of the Leicester Cough Questionnaire in bronchiectasis

BACKGROUND

The Leicester Cough Questionnaire (LCQ) has been validated for assessing cough-specific health status in bronchiectasis. We translated the LCQ into Mandarin Chinese and investigated its validity, reliability and responsiveness.

METHODS

The LCQ was translated into Mandarin Chinese using the forward-backward translation procedure. A total of 144 out-patients completed the Mandarin Chinese version of the LCQ (LCQ-MC), the Hospital Anxiety and Depression Scale (HADS) and the St George's Respiratory Questionnaire. Reassessments were performed during exacerbations and at 6 months. Concurrent validation, internal consistency, repeatability and responsiveness were determined.

RESULTS

Minor cultural adaptations were made to the wording of LCQ-MC. No other difficulties were found during the translation process, with all items easily adapted to acceptable Mandarin Chinese. The questionnaire was not changed in terms of content layout and the order of the questions. In cognitive debriefing interviews, participants reported that the questionnaire was acceptable, relevant, comprehensive and easy to complete. The LCQ-MC showed good concurrent validity, internal consistency and test-retest reliability. Responsiveness was shown by significant changes in LCQ-MC scores between steady state, the first exacerbation and following 2-week antibiotic treatment (both interval changes, P < 0.01) CONCLUSION: The LCQ-MC is a valid, reliable and responsive instrument for determining cough-specific health status in Chinese bronchiectasis patients.

Identification of mutations in U2HR in two Chinese families with Marie Unna hereditary hypotrichosis

Marie Unna hereditary hypotrichosis (MUHH) is a rare autosomal dominant genodermatosis characterized by coarse, wiry, twisted hair developing during early childhood, with subsequent progressive hair loss. Recently, mutations in U2HR, an inhibitory upstream open reading frame in the 5' untranslated region of the human hairless gene (HR), were identified as the underlying cause of MUHH. We investigated two unrelated Chinese multigenerational families with MUHH. By sequencing U2HR in the two families, we identified two previously reported mutations, c.1A >T (p.Met1?) and c.104A>G (p*35Wext1263*). Both these mutations cosegregated with the disease phenotype in the two families.

Impact of adherence to GOLD guidelines on 6-minute walk distance, MRC dyspnea scale score, lung function decline, quality of life, and quality-adjusted life years in a Shanghai suburb

We performed a 1-year cluster-randomized field trial to assess the effect of standardized management of chronic obstructive pulmonary disease (COPD) on lung function and quality of life (QOL) measures in patients in China. We used the Global Initiative for Chronic Obstructive Lung Disease (GOLD) treatment guidelines and assessed indexes including pulmonary function, QOL, quality-adjusted life years (QALY), Medical Research Council (MRC) dyspnea scale, 6-min walk distance (6-MWD), number of emergency visits, and frequency of hospitalization. Of a total of 711 patients with chronic cough and asthma, 132 were diagnosed as having COPD and 102 participated in this study [intervention group (N = 47); control group (N = 55)]. We found that adherence to GOLD guidelines had a perceivable impact on 6-MWD, MRC dyspnea scale score, and QOL. The average QALY increased by 1.42/person/year in the intervention group, but declined by 0.95/person/year in the control group. We conclude that standardized management improves disease severity, QOL, and QALY in COPD patients when treatment protocols adhere to GOLD guidelines.

Nomogram for Predicting Time to Death After Withdrawal of Life-Sustaining Treatment in Patients With Devastating Neurological Injury

Reliable prediction of time of death after withdrawal of life-sustaining treatment in patients with devastating neurological injury is crucial to successful donation after cardiac death. Herein, we conducted a study of 419 neurocritical patients who underwent life support withdrawal at four neurosurgical centers in China. Based on a retrospective cohort, we used multivariate Cox regression analysis to identify prognostic factors for patient death, which were then integrated into a nomogram. The model was calibrated and validated using data from an external retrospective cohort and a prospective cohort. We identified 10 variables that were incorporated into a nomogram. The C-indexes for predicting the 60-min death probability in the training, external validation and prospective validation cohorts were 0.96 (0.93-0.98), 0.94 (0.91-0.97), and 0.99 (0.97-1.00), respectively. The calibration plots after WLST showed an optimal agreement between the prediction of time to death by the nomogram and the actual observation for all cohorts. Then we identified 22, 26 and 37 as cut-points for risk stratification into four groups. Kaplan-Meier curves indicated distinct prognoses between patients in the different risk groups (p < 0.001). In conclusion, we have developed and validated a nomogram to accurately identify potential cardiac death donors in neurocritical patients in a Chinese population.

Inflammatory Responses, Spirometry, and Quality of Life in Subjects With Bronchiectasis Exacerbations

BACKGROUND

Bronchiectasis exacerbations are critical events characterized by worsened symptoms and signs (ie, cough frequency, sputum volume, malaise).

OBJECTIVES

Our goal was to examine variations in airway and systemic inflammation, spirometry, and quality of life during steady state, bronchiectasis exacerbations, and convalescence (1 week following a 2-week antibiotic treatment) to determine whether potentially pathogenic microorganisms, including Pseudomonas aeruginosa, were associated with poorer conditions during bronchiectasis exacerbations.

METHODS

Peripheral blood and sputum were sampled to detect inflammatory mediators and bacterial densities. Spirometry and quality of life (St George Respiratory Questionnaire [SGRQ]) were assessed during the 3 stages.

RESULTS

Forty-eight subjects with bronchiectasis (43.2 ± 14.2 y of age) were analyzed. No notable differences in species and density of potentially pathogenic microorganisms were found during bronchiectasis exacerbations. Except for CXCL8 and tumor necrosis factor alpha (TNF-α), serum inflammation was heightened during bronchiectasis exacerbations and recovered during convalescence. Even though sputum TNF-α was markedly higher during bronchiectasis exacerbations and remained heightened during convalescence, the variations in miscellaneous sputum markers were unremarkable. Bronchiectasis exacerbations were associated with notably higher SGRQ symptom and total scores, which recovered during convalescence. FVC, FEV1, and maximum mid-expiratory flow worsened during bronchiectasis exacerbations (median change from baseline of -2.2%, -0.8%, and -1.3%) and recovered during convalescence (median change from baseline of 0.6%, 0.7%, and -0.7%). Compared with no bacterial isolation, potentially pathogenic microorganism or P. aeruginosa isolation at baseline did not result in poorer clinical condition during bronchiectasis exacerbations.

CONCLUSIONS

Bronchiectasis exacerbations are characterized by heightened inflammatory responses and poorer quality of life and spirometry, but not by increased bacterial density, which applies for subjects with and without potentially pathogenic microorganism isolation when clinically stable. (ClinicalTrials.gov registration NCT01761214.).

Assessment by three-dimensional power Doppler ultrasound of cerebral blood flow perfusion in fetuses with congenital heart disease

OBJECTIVES

To use three-dimensional (3D) power Doppler ultrasound to investigate cerebral blood flow perfusion in fetuses with congenital heart disease (CHD).

METHODS

The vascularization index (VI), flow index (FI) and vascularization flow index (VFI) in the total intracranial volume and the main arterial territories (middle cerebral artery (MCA), anterior cerebral artery (ACA) and posterior cerebral artery (PCA)) were evaluated prospectively and compared in 112 fetuses with CHD and 112 normal fetuses using 3D power Doppler. Correlations between the 3D power Doppler indices and neurodevelopment scores at 12 months of age were assessed in a subset of the CHD group, and values were compared with those of controls.

RESULTS

Compared with the controls, the VI, FI and VFI of the total intracranial volume and the three main arteries were significantly higher in fetuses with hypoplastic left heart syndrome and left-sided obstructive lesions (P < 0.001), and the 3D power Doppler values in the ACA territory were significantly higher in fetuses with transposition of the great arteries (P < 0.01). The largest proportional increase in the blood flow perfusion indices in the fetuses with CHD relative to controls was observed in the ACA territory (P < 0.05). Among 41 cases with CHD that underwent testing, the mean Psychomotor Development Index (PDI) and Mental Development Index (MDI) scores were significantly lower than in 94 of the controls that were tested (P < 0.001). Among these CHD cases, total intracranial FI was positively correlated with PDI (r = 0.342, P = 0.029) and MDI (r = 0.339, P = 0.030), and ACA-VI and ACA-VFI were positively correlated with PDI (r = 0.377 and 0.389, P = 0.015 and 0.012, respectively) but were not correlated with MDI (r = 0.243 and 0.203, P = 0.126 and 0.204, respectively).

CONCLUSIONS

Cerebral blood flow perfusion was increased relative to controls in most fetuses with CHD and was associated with neurodevelopment scores at 12 months. Prenatal 3D power Doppler ultrasound might help to identify cases of brain vasodilatation earlier and inform parental counseling.

MiR-26b modulates insulin sensitivity in adipocytes by interrupting the PTEN/PI3K/AKT pathway

BACKGROUND

MicroRNAs (miRNAs) have emerged as epigenetic regulators of metabolism and energy homeostasis. There is a growing body of evidence pointing to miRNAs that have important regulatory roles in insulin sensitivity.

OBJECTIVE

The aim of this work was to explore the expression and mechanism of action of miR-26b in obesity-related insulin resistance (IR) in adipocytes.

METHODS

Quantitative real-time PCR was performed to determine miR-26b expression in obese rodent models, human obesity subjects and insulin-resistant adipocytes. We analysed the roles of miR-26b overexpression and inhibition on glucose uptake in adipocytes. Western blotting was used to detect the levels of protein molecules involved in the phosphoinositide-3-kinase (PI3K) pathway. Bioinformatics and the Dual Luciferase Assay were used to identify the target gene of miR-26b. We assessed the regulatory roles of miR-26b on the phosphatase and tensin homologue (PTEN)/PI3K/AKT pathway and the relationship between miR-26b and the metabolism of human obese subjects.

RESULTS

Levels of miR-26b are reduced in visceral adipose tissue (VAT) in obese rodent models, human obesity and insulin-resistant adipocytes. MiR-26b promotes insulin-stimulated glucose uptake and increases insulin-stimulated glucose transporter type 4 translocation to the plasma membrane in human mature adipocytes. MiR-26b modulates insulin-stimulated AKT activation via inhibition of its target gene, PTEN, and significantly increases insulin sensitivity via the PTEN/PI3K/AKT pathway. The expression level of miR-26b negatively correlates with increasing body mass index and homeostasis model assessment for IR in human obese subjects.

CONCLUSION

Decreased miR-26b expression in VAT may be involved in obesity-related IR by interrupting the PTEN/PI3K/AKT pathway.

Epidemiology of chronic rhinosinusitis: results from a cross-sectional survey in seven Chinese cities

BACKGROUND

Chronic sinusitis (CRS) is a common otorhinolaryngologic disease that is frequently encountered in everyday practice, but there is a lack of precise data regarding the prevalence of CRS in developing countries. We performed a national investigation in China to determine the prevalence and associated factors of CRS.

METHODS

We conducted a cross-sectional investigation in 2012. A stratified four-stage sampling method was used to select participants randomly from seven cities in mainland China. All participants were interviewed face-to-face via a standardized questionnaire. Unconditional logistic regression analyses were conducted to examine the association between smoking and sinusitis after adjusting for socio-demographic factors.

RESULTS

This study included a total of 10 636 respondents from seven cities. The overall prevalence of CRS was 8.0% and ranged from 4.8% to 9.7% in seven centres. Chronic sinusitis affected approximately 107 million people in mainland China. Chronic sinusitis was particularly prevalent among people with specific medical conditions, including allergic rhinitis, asthma, chronic obstructive pulmonary disease and gout. The prevalence was slightly higher among males (8.79%) than females (7.28%) (P = 0.004), and the prevalence varied by age group, ethnicity and marital status and education (P < 0.05), but not by household per capita income or living space (P > 0.05). Both second-hand tobacco smoke and active smoking were independent risk factors for CRS (P = 0.001).

CONCLUSIONS

Chronic sinusitis is an important public health problem in China. Our study provides important information for the assessment of the economic burden of CRS and the development and promotion of public health policies associated with CRS particularly in developing countries.

Genome-wide copy number profiling using high-density SNP array in chickens

Phenotypic diversity is a direct consequence resulting mainly from the impact of underlying genetic variation, and recent studies have shown that copy number variation (CNV) is emerging as an important contributor to both phenotypic variability and disease susceptibility. Herein, we performed a genome-wide CNV scan in 96 chickens from 12 diversified breeds, benefiting from the high-density Affymetrix 600 K SNP arrays. We identified a total of 231 autosomal CNV regions (CNVRs) encompassing 5.41 Mb of the chicken genome and corresponding to 0.59% of the autosomal sequence. The length of these CNVRs ranged from 2.6 to 586.2 kb with an average of 23.4 kb, including 130 gain, 93 loss and eight both gain and loss events. These CNVRs, especially deletions, had lower GC content and were located particularly in gene deserts. In particular, 102 CNVRs harbored 128 chicken genes, most of which were enriched in immune responses. We obtained 221 autosomal CNVRs after converting probe coordinates to Galgal3, and comparative analysis with previous studies illustrated that 153 of these CNVRs were regarded as novel events. Furthermore, qPCR assays were designed for 11 novel CNVRs, and eight (72.73%) were validated successfully. In this study, we demonstrated that the high-density 600 K SNP array can capture CNVs with higher efficiency and accuracy and highlighted the necessity of integrating multiple technologies and algorithms. Our findings provide a pioneering exploration of chicken CNVs based on a high-density SNP array, which contributes to a more comprehensive understanding of genetic variation in the chicken genome and is beneficial to unearthing potential CNVs underlying important traits of chickens.

Enhanced angiogenesis promoted by human umbilical mesenchymal stem cell transplantation in stroked mouse is Notch1 signaling associated

Cellular therapy has provided hope for restoring neurological function post stroke through promoting endogenous neurogenesis, angiogenesis and synaptogenesis. The current study was based on the observation that transplantation of human umbilical cord mesenchymal stem cells (hUCMSCs) promoted the neurological function improvement in stroked mice and meanwhile enhanced angiogenesis in the stroked hemisphere. Grafted hUCMSCs secreted human vascular endothelial growth factor A (VEGF-A). Notch1 signaling was activated after stroke and also in the grafted hUCMSCs. To address the potential mechanism that might mediate such pro-angiogenic effect, we established a hUCMSC-neuron co-culture system. Neurons were subjected to oxygen glucose deprivation (OGD) injury before co-culturing to mimic the in vivo cell transplantation. Consistent with the in vivo data, co-culture medium claimed from hUCMSC-OGD neuron co-culture system significantly promoted the capillary-like tube formation of brain-derived endothelial cells. Moreover, coincident with our in vivo data, Notch 1 signaling activation was detected in hUCMSCs after co-cultured with OGD neurons as demonstrated by the up-regulation of key Notch1 signaling components Notch1 and Notch1 intercellular domain (NICD). In addition, OGD-neuron co-culture also increased the VEGF-A production by hUCMSCs. To verify whether Notch1 activation was involved in the pro-angiogenic effect, γ-secretase inhibitor N-[N-(3,5-difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester (DAPT) was added into the co-culture medium before co-culture. It turned out that DAPT significantly prevented the Notch1 activation in hUCMSCs after co-culture with OGD neurons. More importantly, the pro-angiogenic effect of hUCMSCs was remarkably abolished by DAPT addition as demonstrated by inhibited capillary-like tube formation and less VEGF-A production. Regarding how Notch1 signaling was linked with VEGF-A secretion, we provided some clue that Notch1 effector Hes1 mRNA expression was significantly up-regulated by OGD-neuron co-culturing and down-regulated after additional treatment of DAPT. In summary, our data provided evidence that the VEGF-A secretion from hUCMSCs after being triggered by OGD neurons is Notch1 signaling associated. This might be a possible mechanism that contributes to the angiogenic effect of hUCMSC transplantation in stroked brain.

Down-regulation of miR-205 promotes stemness of hepatocellular carcinoma cells by targeting PLCβ1 and increasing CD24 expression

Hepatocellular carcinoma (HCC) is a particularly lethal form of cancer. Overall survival evenafter liver surgery is unsatisfactory due to high metastatic capacity and recurrence rates. Cancer stem cells (CSCs) were recently proposed to elucidate the molecular mechanism of HCC metastasis and recurrence. In our study, we found that down-regulation of miR-205 promoted stem cell inhibition of HCC.Expression of miR-205 and PLCβ1 was investigated by qRT-PCR. MiR-205 and PLCΒ1 expression were associated with disease free survival(DFS) by log-rank test. Computational predicting software was used to predict potential targets of miR-205. MiR-205 and PLCΒ1 were transfected into cells to analyze the stem cell inhibition. MiR-205 was significantly down-regulated and PLCβ1 dramatically up-regulated in tumors compared with matched tissues (P<0.0001). High miR-205 and low PLCβ1 expression was found to be associated with better DFS. PLCβ1 was one of the potential targets of miR-205 and the dual luciferase report system demonstrated that PLCβ1 was a direct target of miR-205 in cells. When miR-205 and PLCβ1 were transfected into cells, we found that the number of spheres increased and the CD24+ subpopulation of HCC cells dramatically increased.Down-regulation of miR-205 promotes stem cell inhibition of HCC by targeting PLCβ1 and increasing CD24 expression.

Wnt3a promotes human umbilical cord mesenchymal stem cells to differentiate into epidermal-like cells

OBJECTIVE

Mesenchymal stem cells are a population of pluripotent cells that can differentiate into epidermal-like cells under certain conditions. Wnt3a can promote the proliferation and differentiation of stem cells. However, the role of Wnt3a in the differentiation of human umbilical cord mesenchymal stem cells (hUCMSCs) into epidermal-like cells is unknown.

MATERIALS AND METHODS

Third-generation hUCMSCs were cultured in normal medium, epidermal stem cell-conditioned medium, and conditioned medium with added Wnt3a. After culturing for 5 days, the expression of cytokeratin 19 (CK19), an antigen specific for epidermal-like cells, was assessed by immunofluorescence and flow cytometry. The expression of CK19 mRNA was confirmed by reverse transcription-polymerase chain reaction(RT-PCR), and β-catenin expression was detected by western blot.

RESULTS

hUCMSCs differentiated into epidermal-like cells when cultured in conditioned medium as shown by positive immunofluorescence staining for CK19. Flow cytometry showed that the number of cells positive for CK19 in the epidermal stem cell-conditioned medium group was significantly higher than that of control group, but lower than that of the Wnt3a-conditioned group (p < 0.05). RT-PCR showed that the expression level of CK19 mRNA in the conditioned medium group was significantly lower than that of the Wnt3a group (p < 0.01). Westernblots showed that the expression of β-catenin in the conditioned medium group was significantly lower than that of the Wnt3a group (p < 0.01).

CONCLUSIONS

These results suggest that Wnt3a can effectively promote the differentiation of hUCMSCs into epidermal-like cells.

Group 4 metal complexes bearing the aminoborane motif: origin of tandem ring-opening metathesis/vinyl-insertion polymerization

The origin of tandem ring-opening metathesis/vinyl-insertion polymerization using tailored group 4 metal complexes is outlined.

Effects of platelet infusion, anticoagulant and other risk factors on the rehaemorrhagia after surgery of hypertensive cerebral hemorrhage

OBJECTIVE

Our objective is to explore the effect of platelet infusion, anticoagulant and other risk factors on the rehaemorrhagia after surgery of hypertensive cerebral hemorrhage (HCH), and to provide a reference for the prevention and treatment of rehaemorrhagia in patients with HCH.

PATIENTS AND METHODS

The patients with HCH admitted during April, 2007-June, 2012 in our hospital were selected. The general data such as age and gender, disease course, past pathogenic characters, past and present medical history such as treatment, personal history, family history and son on, were collected. The data were analyzed by t test, ANOVA, Chi-squared test and logistic regression analysis.

RESULTS

The application of aspirin and platelets has significant effect on rehaemorrhagia after surgery of HCH: 72 patients received aspirin, of which 14 cases had rehaemorrhagia while 197 patients did not receive aspirin, of which 20 cases had rehaemorrhagia. The difference between these two groups was statistically significant (p < 0.05). 186 patients received platelet infusions, of which 18 cases had rehaemorrhagia whereas among other 83 patients not receiving platelet infusions, 16 cases had rehaemorrhagia. Statistical analysis showed a significant difference between these two groups (p < 0.05). In the univariate logistic regression analysis of related data in patients with rehaemorrhagia after surgery of HCH, diastolic or systolic blood pressure at admission, the time from onset to surgery, coagulation disorder, surgical method, hematoma volume, cerebral hemia, effect of hematoma clearance and GCS at admission were the potential risk factors for rehaemorrhagia after surgery of HCH (p < 0.05). In the multivariate logistic regression analysis of related data in the same patients, diastolic blood pressure at admission (> 120 mmHg), systolic blood pressure at admission (> 200 mmHg), the time from onset to surgery and coagulation disorder were screened out (p < 0.05) to be associated with rehaemorrhagia.

CONCLUSIONS

Aspirin increased the risk of rehaemorrhagia after surgery of HCH. On the contrary, infusion of platelets decreased the risk of rehaemorrhagia and improved the prognosis of patients. High diastolic and/or high systolic blood pressure at admission, ultra-early surgery after onset of HCH and coagulation disorder were related with rehaemorrhagia after operation of HCH. Our results indicate that rehaemorrhagia rate can be decreased by controlling related risk factors.

A comparison study on mental health status between suicide survivors and survivors of accidental deaths in rural China

Suicide has become a major public health problem worldwide. For every suicide there are six suicide survivors, a term referring to family members or friends of a person who has died by suicide. Within the literature there has been ongoing debate regarding the bereavement process and if it differs in survivors of suicide as opposed to survivors of those who have died from accidental death. There are scarcely any published reports on comparison between these two groups of survivors in China. In this study, we aimed to explore the difference of mental health status between suicide survivors and survivors of accidental deaths in China. We used a cross-sectional study design to collect data of survivors. Consecutive sampling was used and 92 suicide survivors and 64 survivors of accidental deaths were interviewed. The Symptom Checklist-90-Revised was used to assess the survivors' mental health status. After controlling for demographic variables and time interval between death and interview, no significant differences were found on mental health status between these two groups of survivors. Several explanations might account for the lack of differences. Further studies employing qualitative measures and suicide-specific instruments are needed to explore the bereavement of Chinese suicide survivors.

Diagnosis of lymph node micrometastasis at the pN₀ stage of lung adenocarcinoma using a combination of markers

This study aimed to detect micrometastatic tumor cells in the lymph nodes of patients with pN0 lung adenocarcinoma using a combination of thyroid transcription factor-1 (TTF-1) expression and cytokeratin 7 (CK7) expression and to investigate the association of lymph node micrometastasis with the clinicopathological characteristics of patients with lung adenocarcinoma. A total of 54 patients with pN0 lung adenocarcinoma and whose primary tumors were positive for both TTF-1 and CK7 expression were included in this study. In total, 893 lymph nodes were obtained from these 54 patients and were analyzed for micrometastasis by immunohistochemical staining with anti-CK7 and anti-TTF-1 antibodies. CK7- and TTF-1-positive cells were found in the lymph nodes of 9 (16.7%) of 54 patients, and 21 (2.4%) of 893 lymph nodes exhibited positivity for these factors. No cells positive for both CK7 and TTF-1 were detected in the 5 lymph nodes obtained from patients with benign lung tumors. Lymph node micrometastasis was found to be associated with the differentiation grade and primary tumor position (P < 0.05). The detection of lymph node micrometastasis by a combination of CK7 and TTF-1 immunohistochemical staining provides a more accurate assessment of tumor staging for pN0 lung adenocarcinoma.

Chromosome 12p13 variants predict recurrence of ischaemic stroke in a Chinese population

BACKGROUND AND PURPOSE

A recent genome-wide association study identified two genetic variants (rs12425791 and rs11833579) on chromosome 12p13 that confer risk of ischaemic stroke. The purpose of this study was to examine whether these two polymorphisms are associated with stroke onset and prognosis in a Chinese population.

METHODS

rs12425791 and rs11833579 were genotyped using the improved multiple ligase detection reaction in 913 patients with ischaemic stroke. Analyses of genotype association with onset and prognosis outcomes were evaluated by the Kaplan-Meier method, the log-rank test and Cox proportional hazards models.

RESULTS

rs12425791 and rs11833579 were not associated with age of stroke onset (P = 0.786 and 0.340, respectively). However, these two polymorphisms were significantly associated with risk of stroke recurrence, especially for the large-artery atherosclerosis (LAA) subtype, in recessive models [hazard ratio (HR) 2.52; 95% confidence interval (CI) 1.04-6.12 for rs12425791; HR 2.13; 95% CI 1.03-4.40 for rs11833579]. The combined genotype of these two single-nucleotide polymorphisms showed a locus-dosage effect on recurrence of LAA subtype and was an independent prognostic factor for LAA subtype in the final multivariate Cox regression model.

CONCLUSIONS

These findings indicated that rs12425791 and rs11833579 on chromosome 12p13 may be useful biomarkers for predicting the prognosis of patients with the LAA subtype of ischaemic stroke.

THz quantum cascade lasers operating on the radiative modes of a 2D photonic crystal

Photonic-crystal lasers operating on Γ-point band-edge states of a photonic structure naturally exploit the so-called "nonradiative" modes. As the surface output coupling efficiency of these modes is low, they have relatively high Q factors, which favor lasing. We propose a new 2D photonic-crystal design that is capable of reversing this mode competition and achieving lasing on the radiative modes instead. Previously, this has only been shown in 1D structures, where the central idea is to introduce anisotropy into the system, both at unit-cell and resonator scales. By applying this concept to 2D photonic-crystal patterned terahertz frequency quantum cascade lasers, surface-emitting devices with diffraction-limited beams are demonstrated, with 17 mW peak output power.

Lentiviral-mediated RNAi targeting caspase-3 inhibits apoptosis induced by serum deprivation in rat endplate chondrocytes in vitro

Current studies find that degenerated cartilage endplates (CEP) of vertebrae, with fewer diffusion areas, decrease nutrient supply and accelerate intervertebral disc degeneration. Many more apoptotic cells have been identified in degenerated than in normal endplates, and may be responsible for the degenerated grade. Previous findings suggest that inhibition of apoptosis is one possible approach to improve disc regeneration. It is postulated that inhibition of CEP cell apoptosis may be responsible for the regeneration of endplates. Caspase-3, involved in the execution phase of apoptosis, is a candidate for regulating the apoptotic process. In the present study, CEP cells were incubated in 1% fetal bovine serum. Activated caspases were detected to identify the apoptotic pathway, and apoptosis was quantified by flow cytometry. Lentiviral caspase-3 short hairpin RNA (shRNA) was employed to study its protective effects against serum deprivation. Silencing of caspase-3 expression was quantified by reverse transcription-polymerase chain reaction and Western blots, and inhibition of apoptosis was quantified by flow cytometry. Serum deprivation increased apoptosis of rat CEP cells through activation of a caspase cascade. Lentiviral caspase-3 shRNA was successfully transduced into CEP cells, and specifically silenced endogenous caspase-3 expression. Surviving cells were protected by the downregulation of caspase-3 expression and activation. Thus, lentiviral caspase-3 shRNA-mediated RNAi successfully silenced endogenous caspase-3 expression, preventing inappropriate or premature apoptosis.

Microbial communities within field-collected Culiseta melanura and Coquillettidia perturbans

Although mosquitoes are well-known vectors of human and animal diseases, pathogens are only minor components of their total endogenous microbial communities. The midguts of many insects, including mosquitoes, contain diverse microbial communities. In this study, we used denaturing gradient gel electrophoresis to identify the diversity of bacteria in field-collected adult female Culiseta melanura (Diptera: Culicidae) (Coquillett) and Coquillettidia perturbans (Diptera: Culicidae) (Walker). Few significant differences in bacterial fauna between the two mosquito species were found, but the results suggest that host life history may be a determinant of the endogenous bacterial communities in mosquitoes. In the present study, the dominant bacteria are frequently identified as major components of other mosquito species' microbial flora, suggesting the establishment of a stable association between the mosquitoes and the microbes after initial acquisition from the environment.

Biomechanical effects of vertebroplasty on thoracolumbar burst fracture with transpedicular fixation: a finite element model analysis

OBJECTIVE

To investigate the biomechanical effects of augmentation of the fractured vertebrae after posterior instrumentation.

METHODS

By simulating internal fixation plus augmentation with cement, eight tridimensional, anatomically detailed finite element models of the T11-L1 functional spinal junction were developed. Two kinds of models for mimicking different severity of the fracture were established according to the Denis' classification. Augmentation with cement was conducted after reduction with posterior fixation using a universal spine system. These models assumed a three-column loading configuration as follows: compression, anteflexion, extension, lateroflexion and axial rotation. Stress of the implants and spine was evaluated.

RESULTS

Data showed that for severely fractured models, augmentation apparently decreased the von Mises stresses by 50% for the rods and 40% for the screws, about 40% for the inferior endplate of T11, and 50% for the superior endplate of L1 in vertical compression and other load situations.

CONCLUSION

We should only apply vertebroplasty to prevent correction loss and implants failure based on the fact that it could significantly decrease stress of the instrumentations and spine when the vertebrae are severely fractured.

LEVEL OF EVIDENCE

Level IV, biomechanical study.

Slc26a3 deficiency is associated with loss of colonic HCO3 (-) secretion, absence of a firm mucus layer and barrier impairment in mice

AIM

Downregulated in adenoma (DRA, Slc26a3) is a member of the solute carrier family 26 (SLC26), family of anion transporters, which is mutated in familial chloride-losing diarrhoea (CLD). Besides Cl(-) -rich diarrhoea, CLD patients also have a higher-than-average incidence of intestinal inflammation. In a search for potential explanations for this clinical finding, we investigated colonic electrolyte transport, the mucus layer and susceptibility against dextran sodium sulphate (DSS)-induced colitis in Slc26a3(-/-) mice.

METHODS

HCO3 (-) secretory (JHCO3 (-) ) and fluid absorptive rates were measured by single-pass perfusion in vivo and in isolated mid-distal colonic mucosa in Ussing chambers in vitro. Colonocyte intracellular pH (pHi ) was assessed fluorometrically, the mucus layer by immunohistochemistry and colitis susceptibility by the addition of DSS to the drinking water.

RESULTS

HCO3 (-) secretory (JHCO3- ) and fluid absorptive rates were strongly reduced in Slc26a3(-/-) mice compared to wild-type (WT) littermates. Despite an increase in sodium/hydrogen exchanger 3 (NHE3) mRNA and protein expression, and intact acid-activation of NHE3, the high colonocyte pH in Slc26a3(-/-) mice prevented Na(+) /H(+) exchange-mediated fluid absorption in vivo. Mucin 2 (MUC2) immunohistochemistry revealed the absence of a firm mucus layer, implying that alkaline secretion and/or an absorptive flux may be necessary for optimal mucus gel formation. Slc26a3(-/-) mice were highly susceptible to DSS damage.

CONCLUSIONS

Deletion of DRA results in severely reduced colonic HCO3 (-) secretory rate, a loss of colonic fluid absorption, a lack of a firmly adherent mucus layer and a severely reduced colonic mucosal resistance to DSS damage. These data provide potential pathophysiological explanations for the increased susceptibility of CLD patients to intestinal inflammation.

Subretinal transplantation of rat MSCs and erythropoietin gene modified rat MSCs for protecting and rescuing degenerative retina in rats

For degenerative retinal diseases, like the acquired form exemplified by age-related macular degeneration (AMD), there is currently no cure. This study was to explore a stem cell therapy and a stem cell based gene therapy for sodium iodate (SI)-induced retinal degeneration in rats. Three cell types, i.e., rat mesenchymal stem cells (rMSCs) alone, erythropoietin (EPO) gene modified rMSCs (EPO-rMSCs) or doxycycline (DOX) inducible EPO expression rMSCs (Tet-on EPO-rMSCs), were transplanted into the subretinal spaces of SI-treated rats. The rMSCs were prepared for transplantation after 3 to 5 passages or modified with EPO gene. During the 8 weeks after the transplantation, the rats treated with rMSCs alone or with two types of EPO-rMSCs were all monitored with fundus examination, fundus fluorescein angiography (FFA) and electroretinogram. The transplantation efficiency of donor cells was examined for their survival, integration and differentiation. Following the transplantation, labeled donor cells were observed in subretinal space and adopted RPE morphology. EPO concentration in vitreous and retina of SI-treated rats which were transplanted with EPO-rMSCs or Tet-on EPO-rMSCs was markedly increased, in parallel with the improvement of retinal morphology and function. These findings suggest that rMSCs transplantation could be a new therapy for degenerative retinal diseases since it can protect and rescue RPE and retinal neurons, while EPO gene modification to rMSCs could be an even better option.

Value of alpha-fetoprotein and clinical characteristics in patients with liver neoplasm

This article aimed to investigate the value of α-fetoprotein (AFP) for the diagnosis of hepatocellular carcinoma (HCC) and to evaluate the relationship between AFP and various clinical variables of HCC comprehensively. A retrospective study of postoperative patients diagnosed with liver neoplasm from two Chinese centers was enrolled in our study.A total of 3050 patients were included. The best cut-off point of AFP for the diagnosis of HCC was 20ng/ml with ideal sensitivity (69.74%), specificity (91.18%), LR (4.12) and YI (0.61). Non-HBV infection patients showed the highest specificity (94.44%) but lowest sensitivity (60.13%). In HBV infection. Patients, HBsAg, HBeAb, and HBcAb positive patients had the highest sensitivity (79.55%) and specificity (58.49%). AFP levels increased significantly in symptomatic patients (p=0.011). Those patients with tumor sizes ≥10cm had much higher serum AFP level compared with smaller tumors ones (p=0.014). AFP levels increased remarkably in patients with vascular invasion (p=0.015). Stepwise logistic regression showed tumor size (≥10cm) was an independent predictor of elevated AFP (OR=2.743, 95%CI: 1.167-6.447, P=0.021). The best discriminating AFP value for the diagnosis of HCC is 20ng/ml; HBsAg, HBeAb and HBcAb positive patients have the optimal sensitivity and specificity; tumor size ≥ 10cm is an independent predictor of elevated AFP.

Genetic variants for type 2 diabetes and new-onset cancer in Chinese with type 2 diabetes

BACKGROUND

Diabetes is associated with an increased risk of cancer. This study aimed to evaluate associations between recently reported type 2 diabetes (T2D) susceptibility genetic variants and cancer risk in a prospective cohort of Chinese patients with T2D.

METHODS

Seven single nucleotide polymorphisms (SNP) in IGF2BP2, CDKAL1, SLC30A8, CDKN2A/B, HHEX and TCF7L2, all identified from genome-wide association studies of T2D, were genotyped in 5900 T2D patients [age mean ± SD = 57 ± 13 years, % males = 46] without any known cancer at baseline. Associations between new-onset of cancer and SNPs were tested by Cox proportional hazard models with adjustment of conventional risk factors.

RESULTS

During the mean follow-up period of 8.5 ± 3.3 years, 429 patients (7.3%) developed cancer. Of the T2D-related SNPs, the G-alleles of HHEX rs7923837 (hazard ratio [HR] (95% C.I.) = 1.34 (1.08-1.65); P = 6.7 ×10(-3) under dominant model) and TCF7L2 rs290481 (HR (95% C.I.) = 1.16 (1.01-1.33); P = 0.040 under additive model) were positively associated with cancer risk, while the G-allele of CDKAL1 rs7756992 was inversely associated (HR (95% C.I.) = 0.80 (0.65-1.00); P = 0.048 under recessive model). The risk alleles of these significant SNPs exhibited combined effect on increasing cancer risk (per-allele HR (95% C.I.) = 1.25 (1.12-1.39); P = 4.8 × 10(-5)). The adjusted cancer risk was 2.41 (95% C.I. 1.23-4.69) for patients with four risk alleles comparing to patients without risk allele.

CONCLUSIONS

T2D-related variants HHEX rs7923837, TCF7L2 rs290481 and CDKAL1 rs7756992 increased cancer risk in patients with diabetes.

IMPACT

Our findings provide novel insights into the pathogenesis of cancer in diabetes.

Effects of common polymorphisms rs2910164 in miR-146a and rs11614913 in miR-196a2 on susceptibility to colorectal cancer: a systematic review meta-analysis

PURPOSE

Emerging evidence has shown that single nucleotide polymorphisms occurred in microRNAs may contribute to the development of colorectal cancer (CRC). rs2910164 in miR-146a and rs11614913 in miR-196a2 are suggested to be associated with the susceptibility to CRC, but individually published studies revealed inconclusive results. To systematically summarize the possible correlationship between these polymorphisms and CRC risk, we performed this meta-analysis.

METHODS

We retrieved the relevant articles of the associations between these two microRNA polymorphisms and susceptibility to CRC for the period up to July 1, 2013. A total of seven articles were identified with 2,143 cases and 2,457 controls for miR-146a rs2910164, 1,594 cases and 2,252 controls for miR-196a2 rs11614913. Odds ratio and 95 % confidence interval were calculated to investigate the strength of the association.

RESULTS

The pooled analysis showed that miR-146a rs2910164 did not reveal any correlation with CRC susceptibility. However, a decreased risk was observed between miR-196a2 rs11614913 and CRC in all genetic models.

CONCLUSION

Our current meta-analysis demonstrates that miR-196a2 rs11614913 most likely contributes to decreased risk of CRC, whereas miR-146a rs2910164 may not be associated with the susceptibility to CRC.

Optimization of in vitro cell labeling methods for human umbilical cord-derived mesenchymal stem cells

BACKGROUND AND OBJECTIVES

Human umbilical cord-derived mesenchymal stem cells (hUCMSCs) are a novel source of seed cells for cell therapy and tissue engineering. However, in vitro labeling methods for hUCMSCs need to be optimized for better detection of transplanted cells.

AIM OF THE STUDY

To identify the most stable and efficient method for labeling hUCMSCs in vitro.

MATERIALS AND METHODS

hUCMSCs were isolated using a modified enzymatic digestion procedure and cultured. hUCMSCs of passage three (P3) were then labeled with BrdU, PKH26, or lentivirus-GFP and passaged further. Cells from the first labeled passage (LP1), the fourth labeled passage (LP4) and later passages were observed using a fluorescence microscope. The differentiation potential of LP4 cells was assessed by induction with adipogenic and osteogenic medium. Flow cytometry was used to measure the percentage of labeled cells and the percentage of apoptotic or dead cells. The labeling efficiencies of the three hUCMSC-labeling methods were compared in vitro.

RESULTS

BrdU, PKH26, and lentivirus-GFP all labeled LP1 cells with high intensity and clarity. However, the BrdU labeling of the LP4 cells was vague and not localized to the cell nuclei; LP9 cells were not detected under a fluorescence microscope. There was also a significant decrease in the fluorescence intensity of PKH26-labeled LP4 cells, and LP11 cells were not detected under a fluorescence microscope. However, the fluorescence of LP4 cells labeled with lentivirus-GFP remained strong, and cells labeled with lentivirus-GFP were detected up to LP14 under a fluorescence microscope. Statistical analyses indicated that percentages of LP1 cells labeled with PKH26 and lentivirus-GFP were significantly higher than that of cells labeled with BrdU (p < 0.05), and that the LP4 cells were more efficiently labeled with lentivirus-GFP than with PKH26 or BrdU (p < 0.05). BrdU-, PKH26-, and lentivirus-GFP labeled LP4 cells were all differentiated to adipocytes or osteoblasts with adipogenic and osteogenic medium. No statistical significance (p > 0.05) was observed between the death rates of labeled and unlabeled cells.

CONCLUSIONS

Lentivirus-GFP is a valid method for long-term in vitro labeling, and it may be used as a long-term hUCMSC tracker following transplantation in vivo.

Therapeutic potential of umbilical cord mesenchymal stem cells with Wnt/β-catenin signaling pathway pre-activated for the treatment of diabetic wounds

The pathogenesis of diabetes mellitus wounds is complicate, and there lacks effective treatment strategies. Mesenchymal stem cells can promote wound healing. Compared with bone marrow mesenchymal stem cells, umbilical cord mesenchymal stem cells have obvious advantages in biological property. Wnts are potent regulatory molecules for stem cell turnover and skin regeneration, while Wnt signaling is not well activated in diabetic wounds. Umbilical cord mesenchymal stem cells with Wnt/β-catenin signaling pathway pre-activated have some potential in the treatment of diabetic wounds. In this paper, we review the research status as well as problems in this field.

Epimorphin-induced differentiation of human umbilical cord mesenchymal stem cells into sweat gland cells

OBJECTIVES

Mesenchymal stem cells (MSCs) have the potential for multi-directional differentiation and can be induced to differentiate into sweat gland cells under certain conditions. Epimorphin (EPM) plays an important role in the promotion of epithelial cell morphogenesis; however, its effect on sweat gland-cell differentiation of MSCs remains unknown. The purpose of this study was to investigate how EPM regulates sweat gland cell differentiation of human umbilical cord mesenchymal stem cells (hUCMSCs).

MATERIALS AND METHODS

hUCMSCs were labeled with 5-bromo-2-deoxyuridine (BrdU) before differentiation induction; were cultured in common culture medium, conditioned medium, or EPM-conditioned medium; and then induced to differentiate into sweat gland cells. Five days after induction, the expression rates of the sweat gland-cell antigens cytokeratin 14 (CK14), cytokeratin 19 (CK19), and carcinoembryonic antigen (CEA) in hUCMSCs were detected by flow cytometry, and the messenger ribonucleic acid (mRNA) and protein levels of CK14, CK19, and CEA were determined by reverse transcription polymerase chain reaction (RT-PCR) and western blot, respectively.

RESULTS

hUCMSCs can be induced to differentiate into sweat gland cells in conditioned medium, and expression of CEA was detected by immunofluorescence assay. Flow cytometry results showed that the expression rate of the sweat gland-cell antigens CK14, CK19, and CEA in the conditioned medium were significantly lower than that in the EPM conditioned medium (p < 0.05). RT-PCR and western blot results showed that the mRNA and protein levels of CK14, CK19, and CEA in the conditioned medium were all significantly lower than that in the EPM-conditioned medium (p < 0.01).

CONCLUSIONS

These results suggest that EPM can effectively induce the differentiation of hUCMSCs into sweat gland cells.

An improved dosage regimen of sertraline hydrochloride in the treatment for premature ejaculation: an 8-week, single-blind, randomized controlled study followed by a 4-week, open-label extension study

WHAT IS KNOWN AND OBJECTIVE

This study aimed at evaluating the safety and efficacy of an improved dosage regimen of sertraline in patients with premature ejaculation (PE) and to examine whether the premature ejaculation diagnostic tool (PEDT) can be used as a measure of treatment response in these patients.

METHODS

A total of 218 PE patients were randomized into control (n = 61) and treatment (n = 157) groups to receive mycelium of cordyceps sinensis C4 and sertraline 50 mg daily for 8 weeks, respectively. Following this blinded stage, sixty-three patients chose to take sertraline 100 mg daily for an additional 4-week period, and 80 other patients continued treatment with sertraline 50 mg. Main outcome measures include intravaginal ejaculatory latency time (IELT), PEDT score and Clinical Global Impression of Change (CGIC) score.

RESULTS

At weeks 4 and 8, mean IELT of patients who subsequently chose to take 100 mg of sertraline was significantly lower than that of patients who continued taking 50 mg of sertraline, although the IELT value was comparable between the two groups of patients at baseline. However, with an additional 4-week treatment, the mean IELT increased significantly more in the 100-mg group than in the 50-mg continuation group. Similar results were also obtained in the analyses of the PEDT and CGIC scores. Both regimens were well tolerated, and relapse rate did not differ significantly between the two groups.

WHAT IS NEW AND CONCLUSION

These findings suggest that PE patients not responding to an 8-week treatment with sertraline 50 mg can benefit from an additional 4-week treatment with sertraline 100 mg and that the PEDT may be a valid measure of treatment response in PE patients.

Biomechanical changes in the pharynx and upper esophageal sphincter after modified balloon dilatation in brainstem stroke patients with dysphagia

BACKGROUND

Few studies have investigated the biomechanical changes in the upper esophageal sphincter (UES) and pharyngeal function after successful dilatation therapy for dysphagia. Using high-resolution manometry (HRM), we examined the biomechanical properties of swallowing in brainstem stroke patients with dysphagia following modified balloon dilation therapy.

METHODS

30 brainstem stroke patients with dysphagia were included. Patients in the experimental group received 3 weeks of modified balloon dilatation treatment and regular dysphagia therapy. Patients in the control group received 3 weeks of regular dysphagia therapy only. Efficacy of treatment was evaluated before and following intervention. Functional oral intake was measured using the Functional Oral Intake Scale (FOIS). Pharyngeal maximum pressures and duration, UES residual pressure and duration during swallowing were measured using HRM.

KEY RESULTS

In the experimental group, the feeding tube was able to be removed in 12 of 15 patients, vs 2 of 15 patients in the control group. The experimental group had 4-point median improvement, while control groups only had 1-point improvement in FOIS scores. In the experimental group, posttreatment UES relaxation and pharyngeal propulsion were both significantly improved for the three materials (p < 0.05) and UES resting pressure approximated normal. In the control group, pharyngeal propulsion was improved for water and thick liquids (p < 0.05) but not for paste material; there was no improvement in posttreatment UES relaxation for all three materials (p > 0.05).

CONCLUSIONS & INFERENCES

Dysphagia therapy with modified dilatation improved UES relaxation, strengthened pharyngeal propulsion, restored UES resting pressure and improved functional oral intake to a greater extent than regular therapy alone.

Dog safety in rural China: children's sources of safety information and effect on knowledge, attitudes, and practices

Dog bites are a significant pediatric public health challenge in rural China. This study evaluated the effect of various sources of dog-safety information on children's knowledge, attitudes, beliefs and practices with dogs. A total of 1925 children (grade 3-6) between 6 and 15 years old in four rural regions across China participated between May and September 2012. Results showed that teachers and especially parents were effective information sources for children to learn about dog safety. Learning from peers and children teaching themselves were ineffective education strategies. Multi-source learning (from both parents and teachers) did not differ from single-source learning (from parents but not teachers) but did exceed learning from teachers but not parents or no learning from adults. Older age was associated with greater safety knowledge but also riskier practices with dogs. Girls generally held more safety knowledge, less risky attitudes/beliefs and safer practices than boys. Neither age nor gender interacted with information sources on outcome measures. In conclusion, parents appear to play a major role in educating children in rural China on dog safety. Future dog safety interventions might focus on changing cognition and behavior as well as delivering basic knowledge to youth through teachers and especially parents.

Predicting skin permeability from complex chemical mixtures: incorporation of an expanded QSAR model

Quantitative structure-activity relationship (QSAR) models have been widely used to study the permeability of chemicals or solutes through skin. Among the various QSAR models, Abraham's linear free-energy relationship (LFER) model is often employed. However, when the experimental conditions are complex, it is not always appropriate to use Abraham's LFER model with a single set of regression coefficients. In this paper, we propose an expanded model in which one set of partial slopes is defined for each experimental condition, where conditions are defined according to solvent: water, synthetic oil, semi-synthetic oil, or soluble oil. This model not only accounts for experimental conditions but also improves the ability to conduct rigorous hypothesis testing. To more adequately evaluate the predictive power of the QSAR model, we modified the usual leave-one-out internal validation strategy to employ a leave-one-solute-out strategy and accordingly adjust the Q(2) LOO statistic. Skin permeability was shown to have the rank order: water > synthetic > semi-synthetic > soluble oil. In addition, fitted relationships between permeability and solute characteristics differ according to solvents. We demonstrated that the expanded model (r(2) = 0.70) improved both the model fit and the predictive power when compared with the simple model (r(2) = 0.21).

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.