Association between PADI4 gene polymorphisms and anti-cyclic citrullinated peptide antibody positive rheumatoid arthritis in a large Chinese Han cohort

OBJECTIVES

The present study was undertaken to investigate the association of peptidyl-arginine-deiminase type IV gene (PADI4) single nucleotide polymorphisms (SNPs) with rheumatoid arthritis (RA) susceptibility, and to determine whether there is any impact of PADI4 polymorphisms on RA subsets or phenotypes in a large Chinese Han cohort.

METHODS

Two PADI4 SNPs (rs2240340 and rs1748033) were genotyped in 1216 Chinese Han RA patients and 1040 unaffected controls by TaqMan SNP Assays. Serum anti-CCP antibody and anti-PAD4 antibody levels were measured by ELISA. Bone destruction was scored by Sharp-van der Heijde scores (SHSs) of hands in 463 patients.

RESULTS

The two SNPs rs2240340 and rs1748033 of PADI4 showed strong association with RA susceptibility (OR=1.23, 95% CI 1.09-1.38, p=6.66×10⁻⁴; and OR=1.24, 95% CI 1.10-1.41, p=6.98×10⁻⁴, respectively). RA risk genotypes of PADI4 were specifically associated with anti-CCP positive RA (rs2240340: p=5.13×10⁻⁶; rs1748033: p=2.97×10⁻³, respectively). Furthermore, there was a trend association between PADI4 rs2240340 and radiographic severity, though it did not reach the statistic significance (p=0.088).

CONCLUSIONS

Our data provide strong evidence that PADI4 polymorphisms are risk factors contributed to RA susceptibility, especially for anti-CCP positive RA, and may confer higher risk of RA radiographic severity in Chinese Han population.

Serum anti-lipocalin 2 IgG is a novel biomarker in the diagnosis of systemic lupus erythematosus

BACKGROUND

Previous work suggests that lipocalin 2 is involved in the pathogenesis of systemic lupus erythematosus (SLE) and that this novel antigen could serve as a high-quality renal biomarker of acute kidney injury in SLE. However, serum lipocalin 2 antibody levels remain unclear. We have therefore undertaken this study to assess the level of serum IgG antibody against lipocalin 2 in different disease states and to evaluate the diagnostic value of this potential biomarker in SLE.

METHODS

Serum levels of anti-lipocalin IgG antibodies were measured by ELISA in 103 SLE patients, 93 rheumatoid arthritis (RA) patients, 29 primary Sjögren's syndrome (pSS) patients, 13 systemic sclerosis (SSc) patients, and 91 healthy controls. Diagnostic properties of anti-lipocalin IgG were determined by receiver-operating characteristic (ROC) curve analysis.

RESULTS

The level of serum anti-lipocalin IgG in patients with SLE was significantly higher than in patients with RA, pSS, SSc, or healthy controls (p < 0.05), effectively distinguishing SLE from other conditions with high sensitivity and specificity (49.5% and 90.7%, respectively). In ROC curve analysis, the area under the curve (AUC) is 0.783, with a 95% confidence interval (CI) extending from 0.729 to 0.839. Anti-lipocalin antibodies were present in 48.1% of anti-Sm-negative SLE patients, and also occurred in SLE patients lacking anti-dsDNA (52%) or anti-nucleosome antibodies (46.3%) antibodies. Finally, SLE patients with positive anti-lipocalin IgG possessed higher levels of IgA and CRP than the negative group (p < 0.05), clearly demonstrating a positive correlation between anti-lipocalin IgG and these laboratory parameters.

CONCLUSIONS

Anti-lipocalin 2 IgG is a promising biomarker for the diagnosis of SLE, particularly when obtained in conjunction with anti-Sm, anti-dsDNA, and anti-nucleosome antibody levels.

Evaluation of simultaneous 201Tl/99mTc dual-isotope cardiac SPECT imaging with model-based crosstalk compensation using canine studies

BACKGROUND

Simultaneous (201)Tl/(99m)Tc-sestamibi dual-isotope myocardial perfusion SPECT imaging can reduce imaging time and produce perfectly registered rest/stress images. However, crosstalk from (99m)Tc into (201)Tl images can significantly reduce (201)Tl image quality. We have developed a model-based compensation (MBC) method to compensate for this crosstalk. The method has previously been validated with phantom and simulation studies. In this study, we evaluated the MBC method using a canine model.

METHODS

Left anterior descending or left circumflex coronary artery stenoses were created in 50 adult mongrel dogs weighing 20-30 kg. The dogs were injected with 111 MBq (3 mCi) of (201)Tl at rest, and a SPECT study acquired. Stress was induced by administering adenosine to the dog, followed by injection of 740 MBq (20 mCi) of (99m)Tc-sestamibi at peak stress. A second SPECT study was performed with data acquired in both (201)Tl and (99m)Tc energy windows to provide simultaneous dual-isotope projection data. The images were reconstructed using the ordered-subsets expectation-maximization reconstruction algorithm with compensation for attenuation, scatter, and detector response. For simultaneously acquired (201)Tl data, we also applied the MBC method to compensate for crosstalk contamination from (99m)Tc.

RESULTS

Without compensation, (99m)Tc crosstalk increased the estimated (201)Tl activity concentration in the rest images and reduced defect contrast. After MBC, the (201)Tl images were in good agreement with the registered single-isotope images and ex vivo count data. The ischemic (IS) to non-ischemic (NIS) region (201)Tl activity concentration ratios were computed for single-isotope and dual-isotope studies. The correlation with ex vivo IS-NIS ratios was 0.815 after MBC, compared to the 0.495 from data without compensation. In addition, the regression line for the IS-NIS ratios with MBC was almost parallel to the line of identity with a slope of 0.93, compared to a slope of 0.45 without compensation.

CONCLUSIONS

These results demonstrate that model-based crosstalk compensation can provide substantial reduction of crosstalk effects in simultaneously acquired myocardial perfusion SPECT images in living biological systems.

Sequence variations at I260 and A1731 contribute to persistent currents in Drosophila sodium channels

Tetrodotoxin-sensitive persistent sodium currents, INaP, that activate at subthreshold voltages, have been detected in numerous vertebrate and invertebrate neurons. These currents are believed to be critical for regulating neuronal excitability. However, the molecular mechanism underlying INaP is controversial. In this study, we identified an INaP with a broad range of voltage dependence, from -60mV to 20mV, in a Drosophila sodium channel variant expressed in Xenopus oocytes. Mutational analysis revealed that two variant-specific amino acid changes, I260T in the S4-S5 linker of domain I (ILS4-S5) and A1731V in the voltage sensor S4 of domain IV (IVS4), contribute to the INaP. I260T is critical for the portion of INaP at hyperpolarized potentials. The T260-mediated INaP is likely the result of window currents flowing in the voltage range where the activation and inactivation curves overlap. A1731V is responsible for impaired inactivation and contributes to the portion of INaP at depolarized potentials. Furthermore, A1731V causes enhanced activity of two site-3 toxins which induce persistent currents by inhibiting the outward movement of IVS4, suggesting that A1731V inhibits the outward movement of IVS4. These results provided molecular evidence for the involvement of distinct mechanisms in the generation of INaP: T260 contributes to INaP via enhancement of the window current, whereas V1731 impairs fast inactivation probably by inhibiting the outward movement of IVS4.

High-intensity focused ultrasound combined with dilatation and curettage for Cesarean scar pregnancy

We describe a new technique for the management of Cesarean scar pregnancy (CSP), high-intensity focused ultrasound (HIFU) combined with dilatation and curettage (D&C), in four patients managed at our university hospital. All four had elevated serum human chorionic gonadotropin (hCG) levels and large lesions with strong peripheral color Doppler signals, indicating possible risk of profuse bleeding, and all four women wished to preserve their fertility. HIFU was performed under local anesthesia. Success of the treatment in all four cases was indicated by complete primary evacuation of the CSP and return of serum hCG to normal levels (serum hCG < 20 mIU/mL). However, one patient in whom there was a large scar defect and placental implantation underwent laparotomy to remove the trophoblastic tissue and repair the defect, although the hCG level had already returned to normal levels. HIFU, by utilizing ultrasound energy to heat tissue at a focal point, is able to stop embryonic cardiac activity and leads to a rapid reduction in serum hCG levels. Subsequent D&C under hysteroscopic guidance enables complete removal of products of conception following the HIFU procedure.

[Prevalence and temporal trend of known diabetes mellitus: results of the German Health Interview and Examination Survey for Adults (DEGS1)]

The first wave of the "German Health Interview and Examination Survey for Adults" (DEGS1, 2008-2011) allows for up-to-date, representative prevalence estimates of known diabetes amongst the 18- to 79-year-old resident population of Germany. Temporal trends can be shown by comparing the survey findings with those of the "German National Health Interview and Examination Survey 1998" (GNHIES98). The definition of known diabetes was based on self-reports in physician-administered interviews that asked respondents if they had ever been diagnosed with diabetes by a doctor or were on anti-diabetic medication. Overall, diabetes had been diagnosed in 7.2 % of the adults (7.4 % of the women; 7.0 % of the men). The prevalence increased substantially with advancing age and was higher in persons of low than of high socioeconomic status. Prevalence varied depending on the type of health insurance held and was highest amongst those insured with AOK health insurance funds. In comparison with GNHIES98, there was a 38 % increase in prevalence, of which approximately one third is to be attributed to demographic ageing. In the context of other nationwide studies, the results indicate a figure of at least 4.6 million 18- to 79-year-olds having been diagnosed with diabetes at some point. Planned analyses of undiagnosed diabetes will contribute to the interpretation of the observed increase in the prevalence of known diabetes. An English full-text version of this article is available at SpringerLink as supplemental.

[Prevalence of dyslipidemia among adults in Germany: results of the German Health Interview and Examination Survey for Adults (DEGS 1)]

Interview and laboratory data from the first wave of the German health interview and examination survey for adults (DEGS1) from 2008 to 2011 were used to provide current estimates of the prevalence of dyslipidemia which are representative of the population in Germany 18 to 79 years of age. A total of 56.6 % of men and 60.5 % of women 18 to 79 years have elevated serum total cholesterol concentrations in excess of the currently recommended threshold of 190 mg/dL; 17.9 % of men and 20.3 % of women have highly elevated total cholesterol concentrations ≥ 240 mg/dL. A total of 19.3 % of men and 3.6 % of women have high density lipoprotein cholesterol concentrations below 40 mg/dL. The overall prevalence of dyslipidemia (total cholesterol ≥ 190 mg/dL or medical diagnosis of dyslipidemia) is 64.5 % for men and 65.7 % for women. Of these, more than half of both men and women have previously undiagnosed dyslipidemia. Among persons with known dyslipidemia, 30.8% take lipid-lowering medication. Dyslipidemia is widely prevalent among adults in Germany. More in-depth analyses will examine time trends in the prevalence of dyslipidemia in Germany and in an international comparison. An English full-text version of this article is available at SpringerLink as supplemental.

Perceptions of caring in China: patient and nurse questionnaire survey

BACKGROUND

The concept of caring is important to both patients and nurses. If patients and nurses perceive caring behaviours differently, patients may not have their needs met or will be dissatisfied with the nursing.

AIM

This study conducted in mainland China compared the perceptions of nurses and patients concerning nurses' caring behaviours.

METHODS

From November 2011 to June 2012, 680 patients and 540 of their nurses in five hospitals in southern, central and eastern China were invited to complete a descriptive comparative survey with four subcategories, the Caring Behaviors Inventory-24. Respondents scored each of the 24 items on the survey from 1 (low) to 6 (high). Of those invited, 595 patients (87.50%) and 445 (82.41%) nurses completed the survey.

RESULTS

The mean item score on the Caring Behaviors Inventory-24 was 4.32 and 4.96 for patients and nurses, respectively. The subcategory with the highest mean score for both groups was knowledge and skills (4.73, 5.25), and the lowest for both groups was positive connectedness (3.98, 4.51). Nurses' scores were significantly higher than those of patients for all four subcategories (P < 0.001).

CONCLUSIONS

The gap between the two groups indicates that nurses need to improve their understanding and response to patients' actual and perceived needs and expectations. In China, patients require more support from nurses of their psychological needs.

STUDY LIMITATIONS

Participants came from a limited number of hospitals in three cities. A larger sample from different hospitals in mainland China could have increased the power of the study.

Proline-rich tyrosine kinase 2 and its phosphorylated form pY881 are novel prognostic markers for non-small-cell lung cancer progression and patients' overall survival

BACKGROUND

Our previous study revealed that proline-rich tyrosine kinase 2 (Pyk2) is implicated in both anchorage-independent growth and anoikis resistance in lung cancer cells. This study aims to explore the expression and clinical significance of Pyk2 and its phosphorylated forms in non-small-cell lung cancer (NSCLC).

METHODS

The mRNA and protein levels of Pyk2 or cancer stem cell markers (ALDH1a1, ABCG2 and Bmi-1) were either examined by reverse transcription-PCR or western blotting. An immunohistochemistry (IHC) assay was conducted to analyse the expression of Pyk2 and its phosphorylated forms in 128 NSCLC cases.

RESULTS

The levels of Pyk2 mRNA, total protein, and its phosphorylated form pY881 were higher in lung cancer lesions than in the paired noncancerous tissues. The IHC analysis showed the levels of the Pyk2 and Pyk2[pY881] proteins were highly expressed in 70 (54.7%) and 77 (60.2%) cases, respectively. Both Pyk2 and Pyk2[pY881] were independent prognostic factors for NSCLC patients. The gain and loss study of Pyk2 function revealed that Pyk2 could upregulate the expression of ALDH1a1, ABCG2 and Bmi-1 and enhance the ability of colony formation in soft agar assay in A549 and H460 cells.

CONCLUSION

Both Pyk2 and phosphorylated Pyk2[pY881] are potential prognostic factors and therapeutic targets for NSCLC.

Intra-articular nuclear factor-κB blockade ameliorates collagen-induced arthritis in mice by eliciting regulatory T cells and macrophages

Nuclear factor (NF)-κB is a transcription factor implicated in the pathogenesis of autoimmune disorders such as rheumatoid arthritis (RA). Here we have examined the effect of intra-articular administration of the IKK inhibitor, NEMO-binding domain peptide (NBD), on the severity of collagen-induced arthritis (CIA). NBD peptides were injected intra-articularly into the knee joints of DBA/1J mice after the onset of disease. Collagen-injected mice given a scrambled peptide served as controls. Arthritis severity was determined by visual examination of paws. Intra-articular NBD injection reduced the arthritis score and ameliorated morphological signs of bone destruction compared to the controls. Serum levels of type-II collagen-specific immunoglobulin (Ig)G2a antibodies were lower in NBD-treated mice versus the control mice, whereas the levels of type-II collagen-specific IgG1 antibodies were increased by NBD treatment. NBD treatment diminished the proinflammatory cytokines interleukin (IL)-17 and interferon (IFN)-γ in serum, but increased the regulatory cytokine IL-10. NBD-treated CIA mice exhibited significantly higher percentages and numbers of forkhead box protein 3 (FoxP3(+)) CD4(+) CD25(+) regulatory T cells than controls. Immunofluorescence analysis of NBD-treated mice revealed that FoxP3 and Ym1, a marker of alternatively activated macrophages, were juxtaposed to each other within draining inguinal lymph nodes. Intra-articular administration of NBD peptide is effective as an experimental therapy in a murine model of RA. Nevertheless, the intra-articular treatment modality is still associated with systemic effects on the immune system.

Gαq gene promoter polymorphisms and rheumatoid arthritis in the Han Chinese population are not associated

Mice that lose Gαq from their immune system can spontaneously develop inflammatory arthritis. Gαq expression in the peripheral blood lymphocytes of rheumatoid arthritis (RA) patients is significantly decreased in comparison to that in healthy individuals, and reduced Gαq expression is closely correlated with RA disease activity. These indicate that Gαq plays critical roles in the pathogenesis of RA. To address whether single nucleotide polymorphism in the promoter region of the Gαq gene (GNAQ) influenced Gαq expression in RA patients and was a genetic risk factor for RA, we sequenced the promoter region of GNAQ in a Han Chinese population. A common dinucleotide polymorphism at position -695/-694, an exchange of 2 adjacent nucleotides (GC>TT), was revealed in 118 RA patients and 101 healthy adults. The proportions of genotypes observed for -695/-694 in the RA group were GC/GC (65.25%), GC/TT (33.05%), and TT/TT (1.70%), and those in the control group were GC/GC (62.38%), GC/TT (33.66%), and TT/TT (3.96%). No significant difference in the allele and genotype frequencies between RA patients and healthy controls for dinucleotide polymorphism was found in the Han Chinese population, neither in the whole data set nor in stratified subsets, i.e., rheumatoid factors, anti-cyclic citrullinated peptide antibody, and Gαq expression status (P > 0.05). We conclude that the GNAQ promoter polymorphism is not a genetic risk factor for RA in the Han Chinese population, and that decreased Gαq expression in peripheral blood lymphocytes of RA might potentially be due to other causes.

Membrane association and destabilization by Aggregatibacter actinomycetemcomitans leukotoxin requires changes in secondary structures

Aggregatibacter actinomycetemcomitans is a common inhabitant of the upper aerodigestive tract of humans and non-human primates and is associated with disseminated infections, including lung and brain abscesses, pediatric infective endocarditis, and localized aggressive periodontitis. Aggregatibacter actinomycetemcomitans secretes a repeats-in-toxin protein, leukotoxin, which exclusively kills lymphocyte function-associated antigen-1-bearing cells. The toxin's pathological mechanism is not fully understood; however, experimental evidence indicates that it involves the association with and subsequent destabilization of the target cell's plasma membrane. We have long hypothesized that leukotoxin secondary structure is strongly correlated with membrane association and destabilization. In this study, we tested this hypothesis by analysing lipid-induced changes in leukotoxin conformation. Upon incubation of leukotoxin with lipids that favor leukotoxin-membrane association, we observed an increase in leukotoxin α-helical content that was not observed with lipids that favor membrane destabilization. The change in leukotoxin conformation after incubation with these lipids suggests that membrane binding and membrane destabilization have distinct secondary structural requirements, suggesting that they are independent events. These studies provide insight into the mechanism of cell damage that leads to disease progression by A. actinomycetemcomitans.

Effect of clopidogrel with or without omeprazole in patients with carotid artery stenting

BACKGROUND

Recent concerns have been raised about the potential for proton pump inhibitors (PPIs) to blunt the efficacy of clopidogrel. We observed the effect of clopidogrel plus aspirin with or without omeprazole in patients with carotid stenoses after they received placement of carotid stents.

METHODS

Sixty-four consecutive patients treated with percutaneous carotid artery stenting (CAS) comprised the sample. All enrolled patients underwent the C13 urea breath test (C13 UBT) before CAS. Patients with Helicobacter pylori infection and a history of peptic ulcer were assigned dual antiplatelet combination with omeprazole. Others received dual antiplatelet without omeprazole. Transcranial Doppler and ultrasonography were performed to assess the middle cerebral artery and carotid artery in follow-up at three months and six months.

RESULTS

Eight patients had gastrointestinal bleeding; the event rate was 22.6% without omeprazole and 3.8% with omeprazole. The rate of gastrointestinal bleeding was reduced with omeprazole as compared without omeprazole (p = 0.026, p < 0.05). The two groups did not differ significantly in the rate of in-stent restenosis and thrombus through transcranial Doppler and ultrasonography.

CONCLUSION

Among patients receiving dual antiplatelet therapy, prophylactic use of omeprazole reduced the rate of upper gastrointestinal bleeding. There was no apparent interaction between clopidogrel and omeprazole in patients with carotid artery stenting.

Effects of alloying element and temperature on the stacking fault energies of dilute Ni-base superalloys

A systematic study of stacking fault energy (γ(SF)) resulting from induced alias shear deformation has been performed by means of first-principles calculations for dilute Ni-base superalloys (Ni(23)X and Ni(71)X) for various alloying elements (X) as a function of temperature. Twenty-six alloying elements are considered, i.e., Al, Co, Cr, Cu, Fe, Hf, Ir, Mn, Mo, Nb, Os, Pd, Pt, Re, Rh, Ru, Sc, Si, Ta, Tc, Ti, V, W, Y, Zn, and Zr. The temperature dependence of γ(SF) is computed using the proposed quasistatic approach based on a predicted γ(SF)-volume-temperature relationship. Besides γ(SF), equilibrium volume and the normalized stacking fault energy (Γ(SF) = γ(SF)/Gb, with G the shear modulus and b the Burgers vector) are also studied as a function of temperature for the 26 alloying elements. The following conclusions are obtained: all alloying elements X studied herein decrease the γ(SF) of fcc Ni, approximately the further the alloying element X is from Ni on the periodic table, the larger the decrease of γ(SF) for the dilute Ni-X alloy, and roughly the γ(SF) of Ni-X decreases with increasing equilibrium volume. In addition, the values of γ(SF) for all Ni-X systems decrease with increasing temperature (except for Ni-Cr at higher Cr content), and the largest decrease is observed for pure Ni. Similar to the case of the shear modulus, the variation of γ(SF) for Ni-X systems due to various alloying elements is traceable from the distribution of (magnetization) charge density: the spherical distribution of charge density around a Ni atom, especially a smaller sphere, results in a lower value of γ(SF) due to the facility of redistribution of charges. Computed stacking fault energies and the related properties are in favorable accord with available experimental and theoretical data.

Abstract P5-10-15: Genetic variants located in beta2 adrenergic receptor gene (ADRB2) and miRNA let-7 binding site alter breast cancer susceptibility: a case control analysis

Previous studies have shown that a potential association may exist between risk of breast cancer and polymorphisms in the beta-adrenergic receptor gene. ADRB2 is a target for miRNA let-7 and it is reported that low let-7 expression probably increases risk of breast cancer. In this study, we investigated the relationship between genetic variants located in alpha2 and beta2 adrenergic receptor genes and miRNA let-7 binding sites with breast cancer risk in benign mammary disease and sporadic breast cancer. We assessed frequency distributions of these variants in 741 patients with histologically confirmed breast cancer and 315 controls with benign mammary disease. We initially demonstrated that rs1042713, located in ADRB2 and rs11292, located in miRNA let-7 binding site were associated with susceptibility to breast cancer. A significant association was observed between GG, AG+GG genotype compared to AA genotype of SNP rs1042713 and a decreased breast cancer risk (adjusted OR = 0.79, 95%CI: 0.64–0.97, p = 0.025; adjusted OR = 0.72, 95%CI: 0.54–0.96, p = 0.028). We also found a significant association between TC, TC+CC genotype compared to TT genotype of SNP rs11292 and an increased breast cancer risk (adjusted OR = 1.44, 95%CI: 1.01–2.06, p = 0.044; adjusted OR = 1.43, 95%CI: 1.01–2.02, p = 0.044). The allele of G of SNP rs1042713 was associated with a decreased risk of breast cancer (OR = 0.79, 95%CI: 0.66–0.96, p = 0.018). Taken together, our study demonstrated that genetic variants located in ADRB2 and miRNA let-7 binding site could alter breast cancer risk.

Keywords: ADRB2 gene, miRNA let-7, polymorphism, breast cancer

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-10-15.

In vivo redox state of human thioredoxin and redox shift by the histone deacetylase inhibitor suberoylanilide hydroxamic acid (SAHA)

The cytosolic thioredoxin (Trx1) system is essential for maintaining a reduced intracellular environment, via reduced Trx1 acting as a general protein disulfide reductase. Trx1 is implicated in cell signaling such as proliferation, DNA synthesis, enzyme activation, cell cycle regulation, transcription, gene activation, and prevention of apoptosis. Human Trx1 contains the active-site cysteines, Cys32 and Cys35, and three additional structural cysteines, Cys62, Cys69, and Cys73, that regulate Trx1 structure and activity via a second disulfide formation, S-glutathionylation or S-nitrosylation. The present study uses an electrophoretic redox Western blot method to analyze the oxidation state of Trx1 in vivo separating the protein-changed isoform following alkylation with iodoacetic acid in 8M urea. Treatment with the histone deacetylase inhibitor SAHA increased Trx1 inhibitor thioredoxin interacting protein (Txnip) levels, decreased Trx1 activity, and switched the Trx1 oxidation state toward a more oxidized one, as a result of complex formation with Trx1, and increased reactive oxygen species (ROS). SAHA is currently in clinical trials for cancer treatment, and one possible mechanism for its anticancer effect is via effects on the Trx1 system. Determining the exact oxidation state of human cytosolic Trx1 may be useful in developing and evaluating cancer drugs and antioxidant agents.