Expression of G protein αq Subunit is Decreased in Lymphocytes from Patients with Rheumatoid Arthritis and is Correlated with Disease Activity

Gαq, the alpha subunit of Gq, a member of the Gq/11 sub-family, was reported to inhibit phosphatidylinositol-3-Kinase (PI3K) activation and prevent the activation of Akt. Previous studies demonstrated that mice losing Gαq in their immune system could spontaneously develop inflammatory arthritis. In this study, we showed that the Gαq expressions at mRNA and protein levels in the peripheral blood lymphocytes (PBLs) from patients with rheumatoid arthritis (RA) were significantly decreased in comparison of which in healthy individuals. The expression levels of Gαq mRNA in PBLs from patients with RA were correlated with RA disease activity (DAS28), anti-cyclic citrullinated protein antibodies, C-reactive protein and rheumatoid factor. We also demonstrated that Gαq controlled the apoptosis of RA PBLs through regulating the activity of Mcl-1 and caspase-3. These data suggested that Gαq might be involved in the pathogenesis of RA by regulating PBLs apoptosis.

The role of autoreactive T cell in the pathogenesis of rheumatoid arthritis and implications for T cell targeted vaccine therapy

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterised by chronic inflammation of joint synovial tissue and subsequent destruction of associated bone, cartilage and soft tissues. RA is commonly treated with non-steroidal anti-inflammatory drugs (NSAIDs), traditional disease-modifying antirheumatic drugs (DMARDs), glucocorticoids and biologic inhibitors of TNF, IL-1, IL-6, T cells and B cells. The use of these drugs especially biological agents has greatly improved the treatment of RA. Although the pathogenesis of RA remains unclear, T-cell mediated immune response is considered as a critical contributor in RA initiation and progression. It has been hypothesized that arthritogenic T cells (autoreactive T cells) escaping negative selection can recognize arthritogenic antigens and lead to autoimmunity and tissue destruction. Due to the important role of autoreactive T cells in the mechanisms of RA, they might be a novel therapeutic target. Many vaccines targeting autoreactive T cells which can establish immunological self tolerance have been developed. The efficacy of these vaccines has been justified in experimental models of RA and clinical trials. Inhibition of autoreactive T cell response by vaccination might provide a new treatment opinion in RA.

Nanodiamonds act as Trojan horse for intracellular delivery of metal ions to trigger cytotoxicity

Background

Nanomaterials hold great promise for applications in the delivery of various molecules with poor cell penetration, yet its potential for delivery of metal ions is rarely considered. Particularly, there is limited insight about the cytotoxicity triggered by nanoparticle-ion interactions. Oxidative stress is one of the major toxicological mechanisms for nanomaterials, and we propose that it may also contribute to nanoparticle-ion complexes induced cytotoxicity.

Methods

To explore the potential of nanodiamonds (NDs) as vehicles for metal ion delivery, we used a broad range of experimental techniques that aimed at getting a comprehensive assessment of cell responses after exposure of NDs, metal ions, or ND-ion mixture: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, Trypan blue exclusion text, optical microscope observation, synchrotron-based scanning transmission X-ray microscopy (STXM) and micro X-ray fluorescence (μXRF) microscopy, inductively coupled plasma-mass spectrometry (ICP-MS), reactive oxygen species (ROS) assay and transmission electron microscopy (TEM) observation. In addition, theoretical calculation and molecular dynamics (MD) computation were used to illustrate the adsorption properties of different metal ion on NDs as well as release profile of ion from ND-ion complexes at different pH values.

Results

The adsorption capacity of NDs for different metal ions was different, and the adsorption for Cu²⁺ was the most strong among divalent metal ions. These different ND-ion complexes then had different cytotoxicity by influencing the subsequent cellular responses. Detailed investigation of ND-Cu²⁺ interaction showed that the amount of released Cu²⁺ from ND-Cu²⁺ complexes at acidic lysosomal conditions was much higher than that at neutral conditions, leading to the elevation of intracellular ROS level, which triggered cytotoxicity. By theoretical approaches, we demonstrated that the functional carbon surface and cluster structures of NDs made them good vehicles for metal ions delivery.

Conclusions

NDs played the Trojan horse role by allowing large amounts of metal ions accumulate into living cells followed by subsequent release of ions in the interior of cells, which then led to cytotoxicity. The present experimental and theoretical results provide useful insight into understanding of cytotoxicity triggered by nanoparticle-ion interactions, and open new ways in the interpretation of nanotoxicity.

Electronic supplementary material

The online version of this article (doi:10.1186/s12989-014-0075-z) contains supplementary material, which is available to authorized users.

High cytoplasmic expression of SALL4 predicts a malignant phenotype and poor prognosis of breast invasive ductal carcinoma

Sal-like 4(SALL4) is significant for maintaining self-renewal and pluripotency in embryonic stem cells, cancer cells and perhaps even cancer stem cells. The expression of SALL4 has been recorded in various kinds of cancers and is deemed to have a clinical value for diagnosis. However, little information on SALL4 expression has been illustrated in breast cancer. In this study, the expression of SALL4 was scrutinized by immunohistochemical analysis in breast invasive ductal carcinoma in a large cohort of 160 patients. High cytoplasmic expression of SALL4 was detected in breast cancer tissues compared with normal adjacent tissues. High SALL4 expression was associated with advanced tumor invasion (p = 0.019), lymph node stage (p = 0.027), ER (p = 0.030), PR (p = 0.037), HER2 (p = 0.019) and TNBC (p = 0.007) in overall patients. Interestingly, in Kaplan-Meier analysis, breast cancer patients with high expression of SALL4 demonstrated a worse OS. Both univariate and multivariate analysis illustrated that examination of SALL4 was of great prognostic value in OS. Thus, our data showed that high cytoplasmic expression of SALL4 was considered to be an independent prognostic indicator for breast invasive ductal carcinoma.

Molecular-scale hydrophilicity induced by solute: molecular-thick charged pancakes of aqueous salt solution on hydrophobic carbon-based surfaces

We directly observed molecular-thick aqueous salt-solution pancakes on a hydrophobic graphite surface under ambient conditions employing atomic force microscopy. This observation indicates the unexpected molecular-scale hydrophilicity of the salt solution on graphite surfaces, which is different from the macroscopic wetting property of a droplet standing on the graphite surface. Interestingly, the pancakes spontaneously displayed strong positively charged behavior. Theoretical studies showed that the formation of such positively charged pancakes is attributed to cation–π interactions between Na⁺ ions in the aqueous solution and aromatic rings on the graphite surface, promoting the adsorption of water molecules together with cations onto the graphite surface; i.e., Na⁺ ions as a medium adsorbed to the graphite surface through cation–π interactions on one side while at the same time bonding to water molecules through hydration interaction on the other side at a molecular scale. These findings suggest that actual interactions regarding carbon-based graphitic surfaces including those of graphene, carbon nanotubes, and biochar may be significantly different from existing theory and they provide new insight into the control of surface wettability, interactions and related physical, chemical and biological processes.

Orbital effect-induced anomalous anion-π interactions between electron-rich aromatic hydrocarbons and fluoride

Anion-π interactions generally exist between an anion and an electron-deficient π-ring because of the electron-accepting character of the ring. In this paper, we report orbital effect-induced anomalous binding between electron-rich π systems and F(-) through anion-π interactions calculated at the MP2/6-31+G(d,p) and ωB97X-D/6-31+G(d,p) levels of theory. We find that anion-π interactions between F(-) and electron-rich π rings increase markedly with increasing number of π electrons and size of the π rings. This is contrary to intuition because anion-π interactions would be expected to gradually decrease because of gradually increasing Coulombic repulsion between the negative charge of the anions and gradually increasing number of π electrons of the aromatic surfaces. Energy decomposition analysis showed that the key to this anomalous effect is the more effective delocalization of negative charge to the unoccupied π* orbitals of larger π rings, which is termed an "orbital effect".

Matrine reduces yeast-to-hypha transition and resistance of a fluconazole-resistant strain of Candida albicans

AIMS

To evaluate the potential effect of matrine on reducing the growth of hypha and lowering the resistance of a fluconazole-resistant colony of Candida albicans.

METHODS AND RESULTS

Candida albicans SC5314 and a fluconazole-resistant C. albicans 215 were used. As for C. albicans SC5314, minimal inhibitory concentration (MIC(80)) and effective concentration (EC(50)) were determined, 1 mg ml(-1) matrine could inhibit nearly 80% of planktonic growth by inverted microscope, 2 mg ml(-1) matrine suppressed 50% of metabolic activity of biofilm by XTT assay, vanishing hypha could be observed on spider agar containing 2 mg ml(-1) matrine, the expressions of three hypha-related genes, namely ALS 3, SUN 41 and PBS 2, were suppressed by 29, 45 and 61% by 2 mg ml(-1) matrine. Also, matrine could lower the resistance of C. albicans 215, in either the free-floating form or the biofilm phenotype.

CONCLUSIONS

Matrine had favourable antifungal potential and might be able to reverse the fluconazole resistance of clinical isolates at relatively high concentration. The anti-candidal performance of matrine could be tightly associated with yeast-to-hypha transition proved by spider agar test and qRT-PCR.

SIGNIFICANCE AND IMPACT OF STUDY

More efforts are needed to find new antifungal agents. Matrine could be a potential candidate to fight against Candida-related infections by regulating yeast-to-hypha transition.

Clinicopathological features and expression of four keratins (K10, K14, K17 and K19) in six cases of eruptive vellus hair cysts

Six cases of eruptive vellus hair cysts (EVHC) were evaluated for histopathology and the immunohistochemical profile of Ki-67 and four keratins (K10, K14, K17 and K19). The pathological hallmark of EVHC was the existence of vellus hair shafts within the cystic cavity, but atypical pathological changes included two or three cysts and a foreign-body granuloma in three cases. Our results demonstrate that atypical pathological changes are not uncommon in EVHC, and indicate that based on keratin expression, it is likely that EVHC is derived from the infrainfundibulum and sebaceous duct.

Cav-1 deletion impaired hematopoietic stem cell function

A tightly controlled balance between hematopoietic stem and progenitor cell compartments is required to maintain normal blood cell homeostasis throughout life, and this balance is regulated by intrinsic and extrinsic cellular factors. Cav-1 is a 22-kDa protein that is located in plasma membrane invaginations and is implicated in regulating neural stem cell and embryonic stem cell proliferation. However, the role of Cav-1 in hematopoietic stem cell (HSC) function is largely unknown. In this study, we used Cav-1^−/− mice to investigate the role of Cav-1 in HSCs function during aging. The results showed that Cav-1^−/− mice displayed a decreased percentage of B cells and an increased percentage of M cells in the bone marrow and peripheral blood, and these changes were due to an increased number of HSCs. FACS analysis showed that the numbers of Lin⁻Sca1⁺c-kit⁺ cells (LSKs), long-term HSCs (LT-HSCs), short-term HSCs and multipotent progenitors were increased in Cav-1^−/− mice compared with Cav-1^+/+ mice, and this increase became more pronounced with aging. An in vitro clonogenic assay showed that LT-HSCs from Cav-1^−/− mice had reduced ability to self-renew. Consistently, an in vivo competitive transplantation assay showed that Cav-1^−/− mice failed to reconstitute hematopoiesis. Moreover, a Cav-1 deletion disrupted the quiescence of LSKs and promoted cell cycle progression through G2/M phase. In addition, we found that Cav-1 deletion impaired the ability of HSCs to differentiate into mature blood cells. Taken together, these data suggest that Cav-1-deficient cells impaired HSCs quiescence and induced environmental alterations, which limited HSCs self-renewal and function.

Early prediction of response of sorafenib on hepatocellular carcinoma by CT perfusion imaging: an animal study

OBJECTIVE

This study evaluated the feasibility of CT perfusion parameters for the early efficacy prediction of sorafenib in the treatment of hepatocellular carcinoma (HCC) in rats.

METHODS

CT hepatic perfusion measurements were performed in the livers of 40 rats implanted with rat HCC. The rats in the experimental group (n = 28) were treated by oral gavage with sorafenib (20 mg per day), whereas the rats in the control group (n = 12) were treated by normal saline. Rats were classified into the responder group if the maximum diameter of their tumour had decreased 21 days after treatment, whereas the other rats were classified into the non-responder group. Data were analysed using the Pearson correlation analysis or analysis of variance.

RESULTS

CT perfusion was used to depict haemodynamic changes before and after treatment. The arterial liver perfusion was significantly decreased in the responder group on Day 11 after treatment with sorafenib (from 71.5 to 53.4 ml min(-1) 100 ml(-1)), whereas no significant changes were observed in the non-responder group (p = 0.87). The maximum diameter of the tumour was also significantly decreased in the responder group on Day 21 after treatment (p = 0.042), whereas the maximum tumour diameter was significantly increased in the control group (p = 0.001). CONCLUSION AND ADVANCES IN KNOWLEDGE: CT perfusion could be used to quantitatively analyse the haemodynamic changes in the treatment of HCC with sorafenib, which indicates that this approach may be developed for the early prediction of treatment efficacy for sorafenib.

Leptin levels in patients with psoriasis: a meta-analysis

BACKGROUND

There have been inconsistent results reported for leptin levels in patients with psoriasis.

AIM

To evaluate leptin levels in patients with psoriasis using a meta-analysis of studies comparing leptin levels in controls and in patients with psoriasis.

METHODS

PubMed (MEDLINE), EMBASE and the Cochrane Library were searched for relevant papers published in English. Pooled weighted mean differences (WMDs) and 95% CIs were calculated using random-effects and fixed-effects models. Heterogeneity between studies was assessed using the Cochran Q and I(2) statistics.

RESULTS

In total, 11 studies, comprising 773 patients with psoriasis and 570 healthy controls, were identified. Leptin levels were significantly higher in patients with psoriasis compared with controls (WMD = 7.24, 95% CI 4.55-9.93; P < 0.001). On stratified analysis, significant differences in leptin levels between patients with psoriasis and controls were reported only in serum samples (P < 0.001), and not in plasma samples (P = 0.025). Sensitivity analysis showed that there were no changes in the direction of effect when any one study was excluded. No publication bias was detected.

CONCLUSIONS

Leptin levels are higher in patients with psoriasis compared with those in controls. Future studies are warranted to clarify the association between leptin levels and the pathomechanism of psoriasis.

Iodine quantification with dual-energy CT: phantom study and preliminary experience with VX2 residual tumour in rabbits after radiofrequency ablation

OBJECTIVE

The purpose of our study was to validate iodine quantification in a phantom study with dual-source dual-energy CT (DECT) and to apply this technique to differentiate benign periablational reactive tissue from residual tumour in VX2 carcinoma in rabbits after radiofrequency ablation (RFA).

METHODS

We applied iodine quantification with DECT in a phantom and in VX2 carcinoma in rabbits after incomplete RFA to differentiate benign periablational reactive tissue from residual tumour and evaluated its efficacy in demonstrating response to therapeutic RFA. A series of tubes containing solutions of varying iodine concentration were scanned with DECT. The iodine concentration was calculated and compared with known true iodine concentration. Triple-phase contrast-enhanced DECT data on 24 rabbits with VX2 carcinoma were then assessed at Day 3 (n=6), 1 week (n=6), 2 weeks (n=6) and 3 weeks (n=6) after incomplete RFA independently by 2 readers. Dual-energy postprocessing was used to produce iodine-only images. Regions of interest were positioned on the iodine image over the lesion and, as a reference, over the aorta, to record iodine concentration in the lesion and in the aorta. The pathological specimens were sectioned in the same plane as DECT imaging, and the lesion iodine concentration and lesion-to-aorta iodine ratio of residual tumour and benign periablational reactive tissue were assessed.

RESULTS

There was excellent correlation between calculated and true iodine concentration (r=0.999, p<0.0001) in the phantom study. The lesion iodine concentration and lesion-to-aorta iodine ratio in residual tumour were significantly higher than in benign periablational reactive tissue in the 2-week group during the arterial phase (AP) (p<0.01) and in the 3-week group during both the AP (p<0.05) and the portal venous phase (p<0.05). There was no significant difference between them with respect to the lesion iodine concentration or lesion-to-aorta iodine ratio in the 3-day and 1-week groups.

CONCLUSION

Iodine quantification with DECT is accurate in a phantom study and can be used to differentiate benign periablational reactive tissue from residual tumour in VX2 carcinoma in rabbits after RFA.

ADVANCES IN KNOWLEDGE

Iodine quantification with DECT may help in differentiating benign periablational reactive tissue from residual tumour in VX2 carcinoma in rabbits after RFA.

Regulation of epidermal growth factor receptor signaling by plasmid-based microRNA-7 inhibits human malignant gliomas growth and metastasis in vivo

MicroRNAs are endogenous, non-coding RNAs of approximately 20-22 nucleotides that regulate genes expression by binding to the 3' untranslated region (UTR) of targets mRNAs and play critical roles in cancer pathways. Malignant glioma is the most common and highly lethal central nervous system tumor for which little effective treatment is available over several decades. The purpose of this study was to explore the therapeutic potential of plasmid-based microRNA-7 (miR-7) for gliomas in vivo. Enhancing miR-7 levels in vitro could significantly induce cell apoptosis, and inhibit cell proliferation, cell migration and invasion. Western blotting analysis was performed, which indicated that miR-7 directly inhibited epidermal growth factor receptor (EGFR) and further antagonized the downstream protein kinases including ERK, Akt and Stat3. Furthermore, systemic administration of miR-7 encapsulated in cationic liposome resulted in glioma xenografts growth arrest and the metastatic nodules decrease effectively in a sequence-specific manner. In this study, miR-7 was applied in glioma treatment for the first time in vivo. Our findings suggested that the plasmid-mediated gene therapy with miR-7 appeared to be a promising candidate for the development of new antitumor and anti-metastasis treatment for human glioma.

Case-control study of risk factors for human infection with influenza A(H7N9) virus in Jiangsu Province, China, 2013

We describe a case-control study performed in Jiangsu, China, to evaluate risk factors for human infection with novel avian influenza A(H7N9) virus. Twenty-five cases and 93 controls matched by age, sex, and location were included in the study. Direct contact with poultry or birds in the two weeks before illness onset, chronic medical conditions (hypertension excluded), and environment-related exposures were significantly associated with A(H7N9) infection.

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.