Association between copy number variations of HLA-DQA1 and ankylosing spondylitis in the Chinese Han population

Ankylosing spondylitis (AS) is a chronic inflammatory disease with complex genetic traits. Multiple sequence variations have been associated with AS, but explained only a proportion of heritability. The studies herein aimed to explore potential associations between genomic copy number variation (CNV) and AS of Han Chinese. Five AS patients were examined with the high-density comparative genomic hybridization (CGH) microarrays in the first screen test for AS associated CNVs. A total of 533 AS patients and 792 unrelated controls were examined in confirmation studies with the AccuCopy assays. A significant association was observed between the CNV of the HLA-DQA1 and AS. Comparing with controls, AS patients showed an aberrant copy number (CN), and significantly increased number of patients had more than 2 copies of the HLA-DQA1. Therefore, CNV of the HLA-DQA1 may play an important role in susceptibility to AS in Han Chinese population.

Cell wall degradation and the dynamic changes of Ca2+ and related enzymes in the developing aerenchyma of wheat (Triticum aestivum L.) under waterlogging

This research was aimed to study the cell wall degradation and the dynamic changes of Ca2+ and related enzymes in developing aerenchyma of wheat root under waterlogging. An examination of morphological development by light and electron microscope revealed that the structure of cell wall in middle cortical cells remained intact after 12 h of waterlogging and turned thinner after waterlogging for 24 h. At 48 h, the aerenchyma has been formed. The cellulase activity gradually increased in middle cortical cells within 24 h of waterlogging, and decreased with the formation of aerenchyma. Fluorescence detection and subcellular localization of Ca2+ showed the dynamic changing of Ca2+ at the cellular and subcellular levels during the development of aerenchyma. The activity of Ca2+-ATPase enhanced markedly in intercellular space, plasma membrane and tonoplast of some middle cortical cells after 8 h of waterlogging and remained high after 24 h, but it decreased after 48 h of waterlogging. All these suggests that cellulase, Ca2+ and Ca2+-ATPase show a dynamic distribution during the aerenchyma development which associated with the cell wall degradation of middle cortical cells. Moreover, there is a feedback regulation between Ca2+ and Ca2+-ATPase.

1:4 matched case-control study on influential factor of early onset neonatal sepsis

BACKGROUND

Bacteria, funghi, viruses and protozoa can lead to neonatal sepsis. Neonatal sepsis is the leading cause of infectious disease onset and death in many neonates.

AIM

To explore the major risk factors of early-onset neonatal sepsis and provide a scientific basis for strategies of early-onset neonatal sepsis prevention.

SUBJECTS AND METHODS

A 1:4 matched case-control study was adopted and 147 cases of early-onset neonatal sepsis were enrolled. Conditional logistic regression model was used to analyze the univariate and multivariate data to estimate the odds ratio (OR) and the 95% confidence interval (95% CI).

RESULTS

Univariate analysis shows that the impact factors on the occurrence of early-onset neonatal sepsis include the following: Maternal age > 35, mother having fixed occupation, mother of urban residence, abnormal fetal position, fetal times, parity, caesarean section, premature rupture of membranes, amniotic fluid volume abnormalities, pregnancy-induced hypertension, placental abnormalities, fetal distress, newborn gender, low birth weight infants, neonatal Apgar scoring at one and five minutes, neonatal jaundice, wet lung, anemia, IVH, and premature infant. Multivariate logistic regression analysis showed that maternal age > 35 (OR = 4.835, OR 95% CI = 1.170-19.981), cesarean section (OR = 0.103, OR 95% CI = 0.041-0.258), premature rupture of membranes (OR = 0.207, OR 95% CI = 0.078-0.547), premature infants (OR = 0.059, OR 95% CI = 0.010-0.329) and newborn jaundice (OR = 0.092, OR 95% CI = 0.021-0.404) were the factors of early-onset neonatal sepsis.

CONCLUSIONS

Early-onset neonatal sepsis could be affected by multi-factors, and targeted prevention may reduce the incidence of early-onset neonatal sepsis rates.

Efficient 3D porous microstructure reconstruction via Gaussian random field and hybrid optimization

Obtaining an accurate three-dimensional (3D) structure of a porous microstructure is important for assessing the material properties based on finite element analysis. Whereas directly obtaining 3D images of the microstructure is impractical under many circumstances, two sets of methods have been developed in literature to generate (reconstruct) 3D microstructure from its 2D images: one characterizes the microstructure based on certain statistical descriptors, typically two-point correlation function and cluster correlation function, and then performs an optimization process to build a 3D structure that matches those statistical descriptors; the other method models the microstructure using stochastic models like a Gaussian random field and generates a 3D structure directly from the function. The former obtains a relatively accurate 3D microstructure, but computationally the optimization process can be very intensive, especially for problems with large image size; the latter generates a 3D microstructure quickly but sacrifices the accuracy due to issues in numerical implementations. A hybrid optimization approach of modelling the 3D porous microstructure of random isotropic two-phase materials is proposed in this paper, which combines the two sets of methods and hence maintains the accuracy of the correlation-based method with improved efficiency. The proposed technique is verified for 3D reconstructions based on silica polymer composite images with different volume fractions. A comparison of the reconstructed microstructures and the optimization histories for both the original correlation-based method and our hybrid approach demonstrates the improved efficiency of the approach.

Enhancer of zeste homolog 2 activates wnt signaling through downregulating CXXC finger protein 4

Through silencing tumor suppressor genes, epigenetic changes can activate signaling pathways important to cancer development. In this report, we found an epigenetic contribution to the aberrant activation of wnt signaling in human gastric cancer. CXXC4 (CXXC finger protein 4) was identified as a novel target of EZH2 (enhancer of zeste homolog 2), and EZH2 promotes the activation of wnt singaling by downregulating CXXC4 expression. CXXC4 inhibits the growth of gastric cancer cells both in vitro and in vivo through inactivating wnt signaling. In contrast, depletion of CXXC4 activates wnt signaling and promotes the anchorage-independent growth of nontumor gastric epithelial cells. CXXC4 is downregulated in gastric carcinoma tissues and its downregulation is associated with poor outcome of gastric cancer patients (hazard ratio: 5.053, P<0.05). Through its binding to dishevelled (Dvl), CXXC4 stabilizes the destruction complex of β-catenin to inhibit wnt signaling. Two critical amino acid residues in CXXC4, K161 and T162 were found to be important to its binding to Dvl and the growth inhibitory effect of CXXC4. In summary, EZH2 promotes the activation of wnt signaling in gastric carcinogenesis through the downregulation of CXXC4 expression. CXXC4 is a novel potential tumor suppressor directly regulated by EZH2, and its expression is a significant prognosis factor for patients with early stages of gastric cancer.

Differences in brain responses between lean and obese women to a sweetened drink

BACKGROUND

Ingestion of sweet food is driven by central reward circuits and restrained by endocrine and neurocrine satiety signals. The specific influence of sucrose intake on central affective and reward circuitry and alterations of these mechanisms in the obese are incompletely understood. For this, we hypothesized that (i) similar brain regions are engaged by the stimulation of sweet taste receptors by sucrose and by non-nutrient sweeteners and (ii) during visual food-related cues, obese subjects show greater brain responses to sucrose compared with lean controls.

METHODS

In a double-blind, crossover design, 10 obese and 10 lean healthy females received a sucrose or a non-nutrient sweetened beverage prior to viewing food or neutral images. BOLD signal was measured using a 1.5 Tesla MRI scanner.

KEY RESULTS

Viewing food images after ingestion of either drink was associated with engagement of similar brain regions (amygdala, hippocampus, thalamus, anterior insula). Obese differed from lean subjects in behavioral and brain responses rating both beverages as less tasteful and satisfying, yet demonstrating greater brain responses. Obese subjects also showed engagement of an additional brain network (including anterior insula, anterior cingulate, hippocampus, and amygdala) only after sucrose ingestion.

CONCLUSIONS & INFERENCES

Obese subjects had a reduced behavioral hedonic response, yet a greater engagement of affective brain networks, particularly after sucrose ingestion, suggesting that in obese subjects, lingual and gut-derived signaling generate less central hedonic effects than food-related memories in response to visual cues, analogous to response patterns implicated in food addiction.

Magnetoplasmons in quasineutral epitaxial graphene nanoribbons

We present an infrared transmission spectroscopy study of the inter-Landau-level excitations in quasineutral epitaxial graphene nanoribbon arrays. We observed a substantial deviation in energy of the L(0(-1)) → L(1(0)) transition from the characteristic square root magnetic-field dependence of two-dimensional graphene. This deviation arises from the formation of an upper-hybrid mode between the Landau-level transition and the plasmon resonance. In the quantum regime, the hybrid mode exhibits a distinct dispersion relation, markedly different from that expected for conventional two-dimensional systems and highly doped graphene.

Combined treatment of the experimental human papilloma virus-16-positive cervical and head and neck cancers with cisplatin and radioimmunotherapy targeting viral E6 oncoprotein

BACKGROUND

Human papilloma virus (HPV) is implicated in >99% of cervical cancers and ∼40% of head and neck squamous cell carcinoma (HNSCC). We previously targeted E6 oncogene with (188)Rhenium-labelled monoclonal antibody (mAb) C1P5 to HPV16 E6 in cervical cancer and HNSCC. Intranuclear E6 can be accessed by mAbs in non-viable cells with leaky membranes. As radioimmunotherapy (RIT) efficacy depends on the availability of target protein-we hypothesised that pretreatment with cisplatin will kill some tumour cells and increase E6 availability for RIT.

METHODS

Mice with subcutaneous HPV16+ cervical (CasKi) and HNSCC (2A3) tumours were pretreated with 0-7.5 mg kg(-1) per day cisplatin for 3 days followed by (188)Re-C1P5 and biodistribution was performed 24 h later. For RIT, the animals were treated with: 5 mg kg(-1) per day cisplatin for 3 days; or 5 mg kg(-1) per day cisplatin for 3 days followed 200 or 400μCi (188)Re-C1P5 mAb; or 200 or 400μCi (188)Re-C1P5 mAb; or left untreated, and observed for tumour growth for 24 days.

RESULTS

Pretreatment with cisplatin increased the uptake of (188)Re-C1P5 in the tumours 2.5 to 3.5-fold and caused significant retardation in tumour growth for CasKi and 2A3 tumours in both RIT alone and cisplatin, and RIT groups in comparison with the untreated control and cisplatin alone groups (P<0.05). The combined treatment was more effective than either modality alone (P<0.05).

CONCLUSION

Our study demonstrates that preceding RIT targeting E6 oncogene with chemotherapy is effective in suppressing tumour growth in mouse models of HPV16+ cancers.

Efficacy of Pyrimethamine/Sulfadoxine versus Chloroquine for the Treatment of Uncomplicated Falciparum Malaria in Children Aged Under 5 Years

The children aged under 5 years from vast African areas badly suffer from falciparum malaria and many of them die of this disease. Therapeutic efficacy of anti-malaria drugs, especially pyrimethamine-sulfadoxine (PS) and chloroquine (CQ) to falciparum malaria is frequently evaluated and reported in recent 10 years. Unfortunately, to date, these widespread materials and researches have not been systematically collected and analyzed. In our study, two investigators were employed to widely and independently gather researches on efficacy of PS vs. CQ mono-therapy of falciparum malaria in children aged below 5 years in unpublished and published databases. Meta-analyses were conducted in categories of PS group and CQ group respectively. Pooled OR of PS vs. CQ was 0.11 (95%CI, 0.05-0.24). PS showed higher therapeutic efficacy to falciparum malaria in less-than-5-year children than CQ. Random model was chosen to analyze for the heterogeneity existence between different studies. Subgroup analyses were performed, but heterogeneity was still presented. Heterogeneity might be caused by different resistance of falciparum malaria to PS and CQ in different settings. Malaria type associated with parasite species, basic information of PS and CQ, and PS & CQ resistant malaria control measures were demonstrated and discussed respectively in detail in this article.

278 Jak/Stat3 SIGNALING PROMOTES SOMATIC CELL REPROGRAMMING BY EPIGENETIC REGULATION

Although leukemia inhibitory factor (LIF) maintains the ground state pluripotency of mouse embryonic stem cells and induced pluripotent stem cells (iPSC) by activating the Janus kinase/signal transducer and activator of transcription 3 (Jak/Stat3) pathway, the mechanism remains unclear. Stat3 has only been shown to promote complete reprogramming of epiblast and neural stem cells, and the partially reprogrammed cells (pre-iPSC). We investigated if and how Jak/Stat3 activation promotes reprogramming of terminally differentiated mouse embryonic fibroblasts (MEF). We demonstrated that activated Stat3 not only promotes but is essential for the pluripotency establishment in MEF cell reprogramming. We further demonstrated that, during reprogramming, inhibiting Jak/Stat3 activity blocks demethylation of Oct4 and Nanog regulatory DNA sequences in induced cells, which are marked by suppressed endogenous pluripotent gene expression. These are correlated with significant upregulation of DNA methyltransferase (Dnmt) 1 and histone deacetylases (HDAC) expression, as well as the increased expression of lysine-specific histone demethylase 2 and methyl-CpG binding protein 2. Inhibiting Jak/Stat3 also blocks the expression of Dnmt3L, which is correlated with the failure of retroviral transgene silencing. Furthermore, Dnmt or HDAC inhibitor but not overexpression of Nanog rescues the reprogramming arrested by Jak/Stat3 inhibition or LIF deprivation. Finally, we demonstrated that LIF/Stat3 signal also represents the prerequisite for complete reprogramming of pre-iPSC. We conclude that Jak/Stat3 activity plays a fundamental role in promoting the establishment of pluripotency at the epigenetic level, by facilitating DNA demethylation/de novo methylation and open-chromatin formation during late stage reprogramming.

Prevalence of post-traumatic stress disorder among adolescents after the Wenchuan earthquake in China

BACKGROUND

The Wenchuan earthquake was a catastrophic earthquake in China. The aim of this study is to explore longitudinally the rates of post-traumatic stress disorder (PTSD) and depression in adolescents after the Wenchuan earthquake, and to identify independent predictors of PTSD.

METHOD

PTSD and depression symptoms among adolescents at 6, 12 and 18 months after the Wenchuan earthquake were investigated using the PTSD Checklist Civilian Version and the Beck Depression Inventory (BDI). Subjects in this study included 548 high school student survivors in a local boarding high school.

RESULTS

The rates of PTSD symptoms were 9.7%, 1.3% and 1.6% at the 6-, 12- and 18-month follow-ups, respectively. BDI scores were found to be the best predictor of severity of PTSD at 6, 12 and 18 months. Gender was another variable contributing significantly to PTSD at 6 and 12 months after the earthquake. In the 12-month follow-up, home damage was found to be a predictor of severity of PTSD symptoms. Being a child with siblings was found to be a predictor of severity of PTSD symptoms at 12 and 18 months after the earthquake.

CONCLUSIONS

PTSD symptoms changed gradually at various stages after the earthquake. Depression symptoms were predictive of PTSD symptoms in the 18-month follow-up study. Other predictors of PTSD symptoms included female gender and being a child with siblings. The results of this study may be helpful for further mental health interventions for adolescents after earthquakes.

Ultrafast surface carrier dynamics in the topological insulator Bi₂Te₃

We discuss the ultrafast evolution of the surface electronic structure of the topological insulator Bi(2)Te(3) following a femtosecond laser excitation. Using time and angle-resolved photoelectron spectroscopy, we provide a direct real-time visualization of the transient carrier population of both the surface states and the bulk conduction band. We find that the thermalization of the surface states is initially determined by interband scattering from the bulk conduction band, lasting for about 0.5 ps; subsequently, few picoseconds are necessary for the Dirac cone nonequilibrium electrons to recover a Fermi-Dirac distribution, while their relaxation extends over more than 10 ps. The surface sensitivity of our measurements makes it possible to estimate the range of the bulk-surface interband scattering channel, indicating that the process is effective over a distance of 5 nm or less. This establishes a correlation between the nanoscale thickness of the bulk charge reservoir and the evolution of the ultrafast carrier dynamics in the surface Dirac cone.

Toward developing a universal treatment for fungal disease using radioimmunotherapy targeting common fungal antigens

BACKGROUND

Previously, we demonstrated the ability of radiolabeled antibodies recognizing the cryptococcal polysaccharide capsule to kill Cryptococcus neoformans both in vitro and in infected mice. This approach, known as radioimmunotherapy (RIT), uses the exquisite ability of antibodies to bind antigens to deliver microbicidal radiation. To create RIT reagents which would be efficacious against all major medically important fungi, we have selected monoclonal antibodies (mAbs) to common surface fungal antigens such as heat shock protein 60 (HSP60), which is found on the surface of diverse fungi; beta (1,3)-glucan, which is a major constituent of fungal cell walls; ceramide which is found at the cell surface, and melanin, a polymer present in the fungal cell wall.

METHODS

MAbs 4E12, an IgG2a to fungal HSP60; 2G8, an IgG2b to beta-(1,3)-glucan; and 6D2, an IgM to melanin, were labeled with the alpha particle emitting radionuclide 213-Bismuth ((213)Bi) using the chelator CHXA". B11, an IgM antibody to glucosylceramide, was labeled with the beta emitter 188-Rhenium ((188)Re). Model organisms Cryptococcus neoformans and Candida albicans were used to assess the cytotoxicity of these compounds after exposure to either radiolabeled mAbs or controls.

RESULTS

(213)Bi-mAbs to HSP60 and to the beta-(1,3)-glucan each reduced the viability of both fungi by 80-100%. The (213)Bi-6D2 mAb to melanin killed 22% of C. neoformans, but did not kill C. albicans. B11 mAb against fungal ceramide was effective against wild-type C. neoformans, but was unable to kill a mutant lacking the ceramide target. Unlabeled mAbs and radiolabeled irrelevant control mAbs caused no killing.

CONCLUSION

Our results suggest that it is feasible to develop RIT against fungal pathogens by targeting common antigens and such an approach could be developed against fungal diseases for which existing therapy is unsatisfactory.

Effect of triptolide on progesterone production from cultured rat granulosa cells

Triptolide(CAS 38748-32-2), a major active component of Tripterygium wilfordii Hook F (TWHF), is known to have multiple pharmacological activities. However, studies have also shown that triptolide is highly disrupt to the reproductive system by disrupting normal steroid hormone signaling. In the present study, we investigated the effect of triptolide (5, 10, or 20 nM for 24 h) on progesterone production by rat granulosa cells. Triptolide inhibited both basal and human chorionic gonadotropin (HCG)- and 8-bromo-cAMP-stimulated progesterone production as revealed by RIA assay. Furthermore, the HCG-evoked increase in cellular cAMP content was also inhibited by triptolide, indicating that disruption of the cAMP/PKA signaling pathway may mediate the deleterious effects of triptolide on progesterone regulation. In addition, triptolide inhibited 25-OH-cholesterol-stimulated progesterone production, suggesting that activity of the P450 side chain cleavage (P450scc) enzyme was also be inhibited by triptolide. Western blot and quantitative real-time PCR (qRT-PCR) assays further revealed that triptolide decreased mRNA and protein expression of P450scc and the steroidogenic regulatory (StAR) protein in granulosa cells. In contrast, cell viability tests using 3-(4,5-dimethyl-thiazol-2-yl)-2,5- diphenyl-tetrazolium bromide (MTT) indicated that triptolide did not cause measurable cell death at doses that suppressed steroidogenesis. The reproductive toxicity of triptolide may be caused by disruption of cAMP/PKA-mediated expression of a number of progesterone synthesis enzymes or regulatory proteins, leading to reduced progesterone synthesis and reproductive dysfunction.

Direct measurement of bend-induced mode deformation in large-mode-area fibers

In 1976 Marcuse developed an equivalent index model to predict the effects of bending in waveguides, and predicted deformation of the spatial modes in bent optical fibers. Perturbative approaches have been previously applied and tested to predict the behavior of single- and few-moded-fibers. However, much more significant mode deformation has been predicted for large-mode-area fibers than for single- or few-moded-fibers. In this paper, the spatial profiles of modes deformed by bending in large-mode-area fibers are measured for the first time. A finite difference method employing the equivalent index model is used to calculate the modes of the helical fiber, which show an offset that is twice as large as that predicted for single-mode fiber, and mode compression that is five times greater. These calculated results are compared to the experimental data, yielding significantly better agreement than previous perturbative approaches.