Magnetoelectrically coupled polariton excitation in a plasmonic crystal composed of nanorod dimers

In this work, the long wavelength optical properties of a plasmonic crystal, composed of gold nanorod dimers arranged parallel, have been studied. Due to the strong coupling between incident light and the oscillation of free electrons inside nanorod dimers, the magnetically induced and/or magnetoelectrically coupled plasmonic polaritons can be excited. A theoretical demonstration has been proposed and coupled equations that show similar profiles to the Huang-Kun equations for ionic crystals have been deduced, indicating the constitutive abnormalities and polaritonic bandgap effect. The analogy between the magnetoelectrically coupled metamaterials and ionic crystals may shed light on physical explanations, as well as constitutive parameter retrieval, for the magnetoelectric metamaterials.

Percutaneous microwave ablation of larger hepatocellular carcinoma

AIM

To evaluate the efficacy and safety of percutaneous microwave ablation (MWA) in patients with larger hepatocellular carcinoma (HCC) tumours.

MATERIALS AND METHODS

Eighty HCC patients with the maximum tumour measuring between 3 and 8 cm were treated using MWA. Of these patients, 57 had initial HCC, while 23 had recurrent HCC. Fifty-two patients had a main tumour measuring 3-5 cm, and 28 had a main tumour measuring 5-8 cm. Local tumour control, complications, long-term survival, and prognostic factors were analysed.

RESULTS

Complete ablation after the initial treatment was achieved in 70 of 80 (87.5%) patients. Sixteen of the 72 (22.2%) successfully treated patients developed local recurrence. Major complications occurred in 7.5% patients. No procedure-related mortality was observed. The 1, 2, 3, and 5 year overall survival rates after the initial ablation were 81.1, 68.2, 56.5, and 34.6%, with a median survival of 56 months. Univariate analysis revealed that small tumour size (p = 0.003) and pre-ablation α-foetoprotein (AFP) level ≤400 ng/ml (p = 0.042) were favourable prognostic factors of overall survival. Multivariate analysis identified only tumour size as the independent prognosis factor (p = 0.008).

CONCLUSION

Percutaneous MWA is effective and safe for treating larger HCC tumours. The local tumour control and long-term survival are acceptable.

Comparison of efficacy between uncovered and covered self-expanding metallic stents in malignant large bowel obstruction: a systematic review and meta-analysis

AIM

Insertion of a self-expandable metallic stent (SEMS) can rapidly relieve colorectal obstruction. This study aimed to compare the efficacy between uncovered and covered SEMSs in the treatment of malignant colorectal obstruction.

METHOD

A systematic search in Medline, Embase, the Cochrane controlled trials register and bibliographies of retrieved articles was performed. Randomized controlled trials and other comparative studies comparing uncovered and covered SEMSs for treatment of malignant colorectal obstruction were selected for this systematic review and meta-analysis. The main outcome measures were technical success, clinical success, tumour ingrowth, tumour overgrowth, early migration (≤ 7 days), late migration (> 7 days), overall complications and the duration of stent patency.

RESULTS

Compared with covered SEMSs, uncovered SEMSs were associated with a lower late migration rate (relative risk 0.25; 95% CI 0.08, 0.80; P = 0.02), a higher tumour ingrowth rate (relative risk 5.99; 95% CI 2.23, 16.10; P = 0.0004) and a prolonged stent patency (weighted mean difference 15.34 days; 95% CI 4.31, 26.37; P = 0.006). There was no significant difference in technical success, clinical success, tumour overgrowth, early migration, perforation or overall complications between the two groups.

CONCLUSION

Tumour ingrowth occurred more frequently in the uncovered SEMS group, while late migration was more common in the covered SEMS group.

Identification and expression analysis of major histocompatibility complex IIB gene in orange-spotted grouper Epinephelus coioides

In this study, complementary DNA (cDNA) and DNA sequences of major histocompatibility complex (MHC) class IIB genes (mhcIIB) were cloned from orange-spotted grouper Epinephelus coioides. The gene structure of E. coioides mhcIIB consists of five exons and four introns, and its deduced amino acid sequence length is 249 amino acids, including a signal peptide, a peptide-binding region, an IGC1 domain, a transmembrane region and a cytoplasmic tail. A phylogenetic study showed that E. coioides mhcIIB shared 32.0-79.1% identity with those of other teleosts and mammals. Real-time reverse transcriptase (RT)-PCR was performed to detect the class IIB gene expression in eight different tissues. To characterize the relationship between E. coioides mhcIIB gene and pathogens, in vivo and in vitro studies were performed. Challenge of Cryptocaryon irritans revealed that class IIB genes were down-regulated after 24 and 48 h of challenge, and their expression was later restored at 72 h. Stimulation of isolated E. coioides leukocytes with lipopolysaccharide (LPS) and polyinosinic:polycytidylic acid (PolyI:C) significantly increased peripheral blood and spleen mhcIIB expression, while head kidney mhcIIB expression remained constant.

OS069. Light, a TNF superfamily member, contributes to pathophysiology in a mouse model of preeclampsia

INTRODUCTION

Preeclampsia (PE) is associated with alterations in the renin-angiotensin system due to the presence of autoantibodies that activate the major angiotensin receptor, AT1R. The resulting chronic activation of the AT1 receptor is believed to contribute to a pro-inflammatory state that is also characteristic of PE. Microarray analysis revealed a pronounced increase in the abundance of LIGHT, a potent member of the TNF superfamily that has emerged as a key factor mediating strong T-cell inflammatory responses and a contributor to autoimmune disease pathogenesis.

OBJECTIVES

The goal of research described here is to determine the contribution of LIGHT to the pathophysiology of PE.

METHODS

An ELISA, specific for LIGHT was used to validate the results of the initial microarray analysis. Infusion experiments were used to determine the effects of elevated LIGHT in pregnant and non-pregnant mice. An adoptive transfer model of PE in pregnant mice was used to determine if AT1R agonistic autoantibodies (AT1AA) stimulate LIGHT production. The potential contribution of increased LIGHT to clinical features of PE in pregnant mice was evaluated by the use of neutralizing antibodies directed to the LIGHT receptors, HVEM and LTβR.

RESULTS

The use of a LIGHT-specific ELISA showed that the cytokine was significantly increased in the circulation and placentas of women with PE. The infusion of recombinant LIGHT into pregnant mice induced major clinical features of PE, including hypertension and proteinuria. Such changes were not observed when LIGHT was infused into not non-pregnant mice. LIGHT was significantly elevated in a pregnant mouse model of PE based on the introduction of IgG from women with PE. In this autoantibody-injection model of PE, the use of neutralizing antibodies to the LIGHT receptors, HVEM and LTβR, blocked autoantibody-induced hypertension, proteinuria, elevated sFlt-1 production, impaired placental angiogenesis and endothelial dysfunction.

CONCLUSION

Overall, our studies show that LIGHT is significantly elevated in women with PE and that elevated LIGHT contributes to pathophysiology of PE in an antibody-injection model of PE in pregnant mice. LIGHT-induced pathophysiology can be abrogated by the use of neutralizing antibodies directed at its receptors, HVEM and LTβR. These results indicate that LIGHT may have a previously unrecognized role in the pathophysiology of PE and that its detrimental effects are pregnancy-dependent. These findings immediately suggest novel therapeutic possibilities.

Downregulation of miR-181a upregulates sirtuin-1 (SIRT1) and improves hepatic insulin sensitivity

AIMS/HYPOTHESIS

Sirtuin-1 (SIRT1) is a potential therapeutic target to combat insulin resistance and type 2 diabetes. This study aims to identify a microRNA (miRNA) targeting SIRT1 to regulate hepatic insulin sensitivity.

METHODS

Luciferase assay combined with mutation and immunoblotting was used to screen and verify the bioinformatically predicted miRNAs. miRNA and mRNA levels were measured by real-time PCR. Insulin signalling was detected by immunoblotting and glycogen synthesis. Involvement of SIRT1 was studied with adenovirus, inhibitor and SIRT1-deficient hepatocytes. The role of miR-181a in vivo was explored with adenovirus and locked nucleic acid antisense oligonucleotides.

RESULTS

miR-181a targets the 3' untranslated region (3'UTR) of Sirt1 mRNA through a miR-181a binding site, and downregulates SIRT1 protein abundance at the translational level. miR-181a is increased in insulin-resistant cultured hepatocytes and liver, and in the serum of diabetic patients. Overexpression of miR-181a decreases SIRT1 protein levels and activity, and causes insulin resistance in hepatic cells. Inhibition of miR-181a by antisense oligonucleotides increases SIRT1 protein levels and activity, and improves insulin sensitivity in hepatocytes. Ectopic expression of SIRT1 abrogates the effect of miR-181a on insulin sensitivity, and inhibition of SIRT1 activity or SIRT1 deficiency markedly attenuated the improvement in insulin sensitivity induced by antisense miR-181a. In addition, overexpression of miR-181a by adenovirus impairs hepatic insulin signalling, and intraperitoneal injection of locked nucleic acid antisense oligonucleotides for miR-181a improves glucose homeostasis in diet-induced obesity mice.

CONCLUSIONS/INTERPRETATION

miR-181a regulates SIRT1 and improves hepatic insulin sensitivity. Inhibition of miR-181a might be a potential new strategy for treating insulin resistance and type 2 diabetes.

WE-E-213CD-09: Multi-Atlas Fusion Using a Tissue Appearance Model

PURPOSE

To improve multi-atlas based auto-segmentation by integrating a tissue appearance model with the Simultaneous Truth and Performance Level Estimation (STAPLE) algorithm to perform multi-atlas fusion.

METHODS

Ten head-and-neck planning CT images were acquired (resolution: 1.0×1.0×2.5mm³ ) and the parotid glands were contoured manually by a head-and-neck oncologist. We performed 10 leave-one-out tests by using one patient as test patient and the rest of 9 patients as atlases. Deformable registration was first applied to transform the atlas parotid contours to the test image one by one. The STAPLE algorithm was initialized by a parotid tissue appearance model, which was estimated from the test image and encoded the intensity information of parotid glands. The individual deformed contours were then fused using the STAPLE algorithm to produce a best approximation of the true contour. The tissue appearance model was also applied to a deformable model segmentation to further refine the fused contours.

RESULTS

The multi-atlas fusion using the tissue appearance model produced an average Dice coefficient of 85.2%±3.1% (left parotid) and 84.9%±3.9% (right parotid) over the 10 tests between the auto-contour and the manual contour, and an average mean surface distance of 1.6±0.3mm and 1.6±0.4mm for left and right parotids respectively. This demonstrated a good agreement between the manual contours and the auto- delineated contours. Our results also showed that, without using the tissue appearance model, the auto-delineated parotid contours might include nearby bony structures; however, using the appearance model was able to correct this problem.

CONCLUSIONS

Including the intensity information using a tissue appearance model into STAPLE algorithm for multi-atlas fusion showed improvement in refining the anatomical boundaries in the multi- atlas based auto-segmentation.

WE-C-217BCD-06: In Vivo Targeting and Imaging of Tumor Vasculature with Radiolabeled, Antibody-Conjugated Nano-Graphene

PURPOSE

Our goal was to explore nano-graphene for in vivo tumor targeting and quantitatively evaluate the pharmacokinetics and tumor targeting efficacy through PET imaging, using ^{6 4} Cu and ⁶⁶ Ga as the radiolabel.

METHODS

Nano-graphene oxide (GO) sheets, with amino group- terminated PEG chains (10 kDa) covalently attached, were conjugated to NOTA (l,4,7-triazacyclononane-l,4,7-triacetic acid, a suitable chelator for ^{6 4} Cu and ^{6 6} Ga) and TRC105 (a mAb that binds to CD 105, overexpressed on neovasculature). FACS analyses, size measurements, and serum stability studies were performed to characterize the GO conjugates before in vivo investigation (PET, bio distribution, blocking studies, etc.) in 4T1 murine breast tumor-bearing mice. Findings from imaging studies were then validated by histology.

RESULTS

TRC105-conjugated GO, 20-30 nm in diameter, was specific for CD105 with little non-specific binding. Both ⁶⁴ Cu- and ⁶⁶ Ga- labled GO conjugates had excellent stability in mouse serum. Clearance of the GO conjugates in mice was via the hepatobiliary pathway. ^v Cu/^{6 6} Ga-NOTA-GO-TRC105 accumulated rapidly in the 4T1 tumor and tumor uptake remained stable over time (3.8±0.4, 4.5±0.4, 5.8±0.3, and 4.5±0.4 %ID/g at 0.5, 3, 7, and 24 h p.i. for⁶⁶ Ga; 5.8±0.6, 5.3±0.6, 4.0±0.4, and3.4±0.1 %ID/g at 0.5, 3,24, and 48 h p.i. for ^{6 4} Cu; n = 4). Blocking studies confirmed CD105 specificity of ^{6 4} Cu/^{6 6} Ga-NOTA- GOTRC105, which was corroborated by bio distribution studies. Furthermore, microscopy examination of GO in light view mode and immunofluorescence staining revealed that targeting of NOTA-GO-TRC105 is tumor vasculature CD105 specific with little extravasation.

CONCLUSIONS

For the first time, we demonstrated that GO can be specifically directed to the tumor neovasculature in vivo through targeting of CD105, a marker of tumor angiogenesis. The versatile chemistry of graphene-based nanomaterials makes them suitable nanoplatforms for future biomedical research, such as cancer theranostics.

WE-C-217BCD-04: Multimodality Imaging of Breast Cancer Experimental Lung Metastasis

PURPOSE

Metastatic breast cancer (MBC) is incurable. The clinical gold standard for assessing tumor microvessel density (MVD), an independent prognostic marker in MBC, is CD 105 staining. The goal of this study is to develop a positron emission tomography (PET)/near-infrared fluorescent (NIRF) probe for imaging of CD105 expression in MBC (i.e. non-invasive measurement of MVD), as well as other applications such as early detection of metastasis, intraoperative guidance, etc.

METHODS

TRC105, a chimeric anti-CD105 mAb, was dual-labeled with a NIRF dye and ⁸⁹ Zr to yield ^{8 9} Zr-Df-TRC105-800CW. Luciferase-transfected 4T1 murine breast cancer cells were injected intravenously into female BALB/c mice to establish a lung MBC model. Bio luminescence imaging (BLI) was carried out to non- invasively monitor the lung tumor burden. Comprehensive in vivo/ex vivo studies were performed to investigate ^{8 9} Zr-Df-TRC105-800CW in this MBC model. Cetuximab was used as an isotype-matched control.

RESULTS

Radiolabeled TRC105 has high tumor uptake in many tumor types in addition to MBC (e.g. pancreatic/prostate cancer and brain tumor), revealing broad clinical potential for TRC105-based agents. FACS analysis of HUVECs showed no difference in CD 105 binding between TRC105 and Df- TRC105-800CW. PET imaging revealed that 4T1 lung tumor uptake of ⁸⁹ Zr-Df-TRC105-800CW was 8.7±1.4,10.9±0.5, and 9.7±1.1 %ID/g at 4, 24, and 48 h post-injection (n = 4), with excellent tumor contrast. Bio distribution studies, blocking, control studies with ^{8 9} Zr-Df-cetuximab- 800CW, ex vivo BLI/PET/NIRF imaging, and histology all confirmed CD 105 specificity of the tracer. NIRF imaging-guided removal of 4T1 tumors with Df-TRC105-800CW in a subcutaneous model was also straightforward.

CONCLUSIONS

We report the first PET/NIRF imaging of CD105 expression in a MBC model. Broad clinical potential of TRC105- based agents was shown in many tumor types, which also enabled early detection of small metastases and provided intraoperative guidance for tumor removal.

Distinct photopolymerization efficacy on dentin of self-etch adhesives

The effect of application mode on polymerization effectiveness of self-etch adhesives with different pHs has rarely been studied. We applied 2 self-etch adhesives-Adper Prompt L-Pop (APLP, pH ~ 0.8) and Adper Easy-Bond (AEB, pH ~ 2.5)-to dentin with or without agitation (dynamic or static application), to investigate photopolymerization efficacy on dentin, and to understand the role of chemical interaction/reaction between adhesives and dentin. Micro-Raman spectra and imaging were acquired across the dentin/adhesive (D/A) interface. The degree of conversion (DC) of each adhesive as a function of position was calculated. SEM-EDS was used to obtain the elemental distribution along the interface. Photopolymerization efficacies of the two self-etch adhesives on dentin were apparently different. APLP exhibited decreasing DCs as the distance from the D/A interface became greater for both application modes, while the DCs for the dynamic mode were much higher than those for the static mode. As for AEB, the DCs remained almost constant across the adhesive layer and showed no significant difference between two modes. Raman spectral analysis disclosed that the chemical interaction between dentin and adhesives was responsible for the observations. We also verified this by tracking the distribution of the elements Ca and P in the adhesive layers.

ENDOGENOUS OPIOID SYSTEM AS A MEDIATOR OF ACUTE AND LONG-TERM ADAPTATION TO STRESS. PROSPECTS FOR CLINICAL USE OF OPIOID PEPTIDES

It has been well established that opioid peptides (OPs) affect various hormonal systems. Opioids exhibit stress-limiting and gastro-protective effects in stressed animals, acting via μ- and δ-opioid receptors (OR). Peripheral μ-OR stimulation by endogenous and exogenous opioids increases cardiac tolerance to pathological consequences of stress. Enhancement of prostacyclin synthesis, decrease of thromboxane production as well as suppression of lipid peroxidation can be directly responsible for cardioprotective effects of OPs in stressed animals. Adaptive responses are accompanied by increased OP levels in blood and tissues. Reduction of ventricular arrhythmias induced by repeated short-term immobilization stress is mediated via μ-OR stimulation by endogenous opioids, while δ-OR account for an antiarrhythmic effect of adaptation to chronic intermittent hypobaric hypoxia. The mechanism of infarct size-limiting effect of continuous normobaric hypoxia involves both μ- and δ-OR stimulation. Peptide OR agonists can be considered in future clinical practice for treatment of withdrawal syndrome, stress-related cardiac disease or myocardial injury caused by ischemia-reperfusion insult. 

First observation of the decay B(c)+ → J/ψπ(+) π- π+

The decay B(c)(+) → J/ψπ(+) π(-) π(+) is observed for the first time, using 0.8 fb(-1) of pp collisions at sqrt[s] = 7 TeV collected by the LHCb experiment. The ratio of branching fractions B(B(c)(+) → J/ψπ(+) π(-) π(+))/B(B(c)(+)→J/ψπ^{+}) is measured to be 2.41 ± 0.30 ± 0.33, where the first uncertainty is statistical and the second is systematic. The result is in agreement with theoretical predictions.

Genetic effects of stearoyl-coenzyme A desaturase (SCD) polymorphism on milk production traits in the Chinese dairy population

Stearoyl-CoA desaturase (SCD) is a multifunctional complex enzyme important in the cellular biosynthesis of fatty acids. The present study was to investigate the association of the SCD gene with milk production traits in dairy cattle. Two single nucleotide polymorphisms (SNPs) (g.6926A>G and g.8646A>G) in introns 3 and 4, and three SNPs (g.10153A>G, g.10213T>C and g.10329C>T) in exon 5 were identified with pooled DNA sequencing and genotyped using matrix-assisted laser desorption/ionization time of flight mass spectrometry assay in 752 Chinese Holstein cows. Polymorphism g.10329C>T was predicted to result in an amino acid replacement from alanine to valine in the SCD protein. With a mixed animal model, the significant associations of the five SNPs with 305-day milk, fat and protein yields and protein percentage were determined. We further demonstrated cows with heterozygous genotypes (A/G or C/T) had highest 305 day milk yield, fat yield, protein yield and lowest protein percentage. Heterozygous cows with genotype AG at the g.6926A>G locus showed the greatest milk yield (P < 0.0001), fat yield (P < 0.0001) and protein yield (P < 0.0001) among other heterozygous genotypes at any of the loci. Dominance effects of all identified SNPs on milk, fat and protein yields and protein percentage were significant. Moreover, significant allele substitution effects at g.6926A>G locus on milk yield and at g.10213T>C on protein yield were observed. Five-locus haplotypes and strong linkage disequilibrium (D' > 0.9) between the five SNPs were also observed. The results suggest that identified polymorphisms could be potential genetic markers to improve the production performance of Chinese Holstein.

Determination of the sign of the decay width difference in the B(s)(0) system

The interference between the K+ K- S-wave and P-wave amplitudes in B(s)(0) → J/ψK+ K- decays with the K+ K- pairs in the region around the ϕ(1020) resonance is used to determine the variation of the difference of the strong phase between these amplitudes as a function of K+ K- invariant mass. Combined with the results from our CP asymmetry measurement in B(s)(0) → J/ψϕ decays, we conclude that the B(s)(0) mass eigenstate that is almost CP = +1 is lighter and decays faster than the mass eigenstate that is almost CP = -1. This determines the sign of the decay width difference ΔΓ(s) ≡ Γ(L) - Γ(H) to be positive. Our result also resolves the ambiguity in the past measurements of the CP violating phase ϕ(s) to be close to zero rather than π. These conclusions are in agreement with the standard model expectations.

Molecular epidemiological features of Mycobacterium tuberculosis in an endemic region of Henan Province, China

Henan Province is one of the regions with the highest tuberculosis (TB) burden in China. Among isolates collected from Zhongmou County, Henan, 21.28% (10/47) of those from 2001 and 22.95% (10/61) from 2007 were resistant to at least one drug (isoniazid, rifampicin, ethambutol or streptomycin); 90.74% (98/108) of the isolates were from the Beijing family, and 108 exhibited 105 different mycobacterial interspersed repetitive units-variable number of tandem repeats patterns. This study preliminarily reveals that Henan Province is still a high prevalence region for drug-resistant TB, and strains collected from local TB cases have diverse genotypes, of which the Beijing family type is predominant.

Immunodiagnostic value of combined detection of autoantibodies to tumor-associated antigens as biomarkers in pancreatic cancer

Previous studies demonstrated that cancer sera contain antibodies, which react with a unique group of autologous cellular antigens called tumour-associated antigens (TAAs). This study determines whether a panel of TAAs would enhance antibody detection and be a useful approach in pancreatic cancer (PC) detection and diagnosis. The panel of TAAs was composed of six TAAs including p53, p16, p62, survivin, Koc and IMP1 full-length recombinant proteins. Enzyme-linked immunosorbent assay (ELISA) was used to detect antibodies against these six TAAs in 23 sera from patients with PC and also 23 sera from normal individuals. Antibody frequency to any individual TAA in PC was variable and ranged from 14.7% to 30.4%. With the successive addition of TAAs to a final total of six antigens, there was a stepwise increase in positive antibody reactions reaching a sensitivity of 60.9% and a specificity of 87.0% in PC. Positive and negative likelihood ratio were 4.685 and 0.449, respectively. Positive and negative predictive values were, respectively, 82.4% and 69.0%. Agreement rate and Kappa value were 73.9% and 0.478, respectively. The data from this study support our previous hypothesis that using a panel of appropriately selected TAAs can enhance autoantibody detection in immunodiagnosis of PC. In 15 PC sera with carbohydrate antigen 19-9 (CA19-9) negative, 6 (40%) were found to have anti-TAA (anti-tumour associated antigens) antibodies. When CA19-9 and anti-TAAs were used together as markers in PC detection, the diagnostic sensitivity could be raised from 60.9% to 69.6%. Anti-TAA and CA19-9 were independent markers, and the simultaneous use of these two markers could raise the sensitivity of PC detection.

Association of KIR genotypes and haplotypes with syphilis in a Chinese Han population

Killer immunoglobulin-like receptors (KIRs) can regulate the activation of NK and T cells in response to infection. Syphilis is a sexually transmitted infection caused by the Treponema pallidum subspecies pallidum spirochete bacterium. The objective of this study was to explore whether KIR genotypes and haplotypes were associated with syphilis in a Chinese Han population. Polymerase chain reaction with sequence-specific primers (PCR-SSP) was used to identify the KIR genotypes in 190 patients with syphilis and 192 healthy controls. The frequency of genotype P was higher in healthy controls than that in patients with syphilis (P = 0.002), and its OR was 0.304, while the frequencies of genotypes AE and AG were higher in patients with syphilis than those in healthy controls. The frequency of haplotype 17 was lower, and its OR was 0.321, whereas the frequencies of haplotype 1 and 6 were higher in patients with syphilis than those in healthy controls. KIR haplotypes A and B have distinctive centromeric (Cen) and telomeric (Tel) gene content motifs. The frequency of Tel-B/B was higher in patients with syphilis than that in healthy controls (P = 0.024). Based on these findings, it seems that individuals with the genotype AE, AG or Tel-B/B, or haplotypes 1 and 6 are susceptible to syphilis, whereas individuals with genotype P or haplotype 17 are protective from syphilis in the Chinese Han population.