Intravenous administration of bone marrow mesenchymal stem cells benefits experimental autoimmune myasthenia gravis mice through an immunomodulatory action

Mesenchymal stem cells (MSC) are potent in immunomodulation. It has been proven that MSC functioned to correct immune disorder in several immune diseases. Here, we tested the hypothesis that MSC from human bone marrow (hMSC) can provide a potential therapy for experimental autoimmune myasthenia gravis (EAMG). EAMG mice model was established by subcutaneous injection of synthetic analogue of acetylcholine receptor (AchR), then, hMSC were intravenously delivered into these mice repeatedly. The results showed that hMSC could specifically home to spleen tissue and hMSC treatment significantly improved the functional deficits of EAMG mice. In addition, AchR antibody level was dramatically decreased in cell-treated group when compared with untreated control on 10 days after the second cell injection. Moreover, both in vivo and in vitro mixed lymphocyte proliferation assays revealed that hMSC could definitely inhibit the proliferation of AchR-specific lymphocyte. In conclusion, our study demonstrated that hMSC treatment was therapeutically useful in autoimmune myasthenia gravis mice, and the underlying mechanism may relate with their immunomodulatory potential.

Cautionary note: linewidth effect in dynamic NMR

In using NMR spectroscopy to evaluate the effects of kinetic processes taking place in the solute molecules being studied, one must estimate the inherent width w of each line, which is hidden from view throughout the kinetic thermal region due to the line-width broadening effected by the processes. We have herein built a self-consistent model function w(T) to attempt to evaluate the variation in the Arrhenius activation energy obtained with the model parameters present in w(T). As it turns out, a sizable number of such line-width parameters yields excellent spectral fits, and these lead to a considerable range of possible activation energies.

Assessment of the Risk of Rupture of Intracranial Aneurysms using Three-Dimensional Cerebral Digital Subtraction Angiography

The aim of this study was to develop an improved binary logistic regression model for predicting the risk of intracranial aneurysm rupture. A cohort of patients ( n = 37) with aneurysms underwent three-dimensional digital subtraction angiography examination to measure several morphological parameters of the aneurysm. The aspect ratio (height/neck size) and the size ratio (length/mean diameter of parent vessel) were also calculated. All the morphological parameters combined with the aneurysm location and the patient's baseline data were used to derive a backward binary logistic regression model. In order to validate the model, it was applied to another independent cohort of 19 patients with aneurysms. The model had sensitivity, specificity and accuracy of 84.6%, 66.7% and 78.9%, respectively. This binary logistic regression model of aneurysm rupture risk identified the status of an aneurysm with high accuracy and could form the basis of more complex models in the future.

Electronic structure of double perovskite A2FeReO6 (A = Ba and Ca): interplay between spin-orbit interaction, electron correlation, and lattice distortion

We have investigated the electronic structure of double perovskites, Ba(2)FeReO(6) (metallic) and Ca(2)FeReO(6) (insulating) using optical and x-ray absorption spectroscopy. By comparing the experimental results with the density functional theory calculations, we found that the electronic structure of Ba(2)FeReO(6) could be determined from the interaction of the electron correlation and spin-orbit coupling. On the other hand, for Ca(2)FeReO(6), the lattice distortion and electron correlation are important in determining the electronic structure. Additionally, the insulating gap in Ca(2)FeReO(6) is realized by the spin-orbit coupling. Our work shows that the subtle interplay of the spin-orbit interaction, electron correlation, and lattice distortion should be taken into account to understand the electronic structure of the 5d transition metal oxides.

Epigenetic inactivation of T-box transcription factor 5, a novel tumor suppressor gene, is associated with colon cancer

T-box transcription factor 5 (TBX5) is a member of a phylogenetically conserved family of genes involved in the regulation of developmental processes. The function of TBX5 in cancer development is largely unclear. We identified that TBX5 was preferentially methylated in cancer using methylation-sensitive arbitrarily primed PCR. We aim to clarify the epigenetic inactivation, biological function and clinical significance of TBX5 in colon cancer. Promoter methylation was evaluated by combined bisulfite restriction analysis and bisulfite genomic sequencing. Cell proliferation was examined by cell viability assay and colony formation assay, apoptosis by flow cytometry and cell migration by wound-healing assay. TBX5 target genes were identified by cDNA microarray analysis. Cox regression model and log-rank test were used to identify independent predictors of prognosis. TBX5 was silenced or downregulated in 88% (7/8) colon cancer cell lines, but was expressed in normal colon tissues. Loss of gene expression was associated with promoter methylation. The biological function of TBX5 in human colon cancer cells was examined. Re-expression of TBX5 in silenced colon cancer cell lines suppressed colony formation (P<0.001), proliferation (P<0.001), migration and induced apoptosis (P<0.01). Induction of apoptosis was mediated through cross-talk of extrinsic apoptosis pathway, apoptotic BCL2-associated X protein and Granzyme A signaling cascades. TBX5 suppressed tumor cell proliferation and metastasis through the upregulation of cyclin-dependent kinase inhibitor 2A, metastasis suppressor 1 and downregulation of synuclein gamma and metastasis-associated protein 1 family member 2. TBX5 methylation was detected in 68% (71/105) of primary colon tumors. Multivariate analysis showed that patients with TBX5 methylation had a significantly poor overall survival (P=0.0007). In conclusion, we identified a novel functional tumor suppressor gene TBX5 inactivated by promoter methylation in colon cancer. Detection of methylated TBX5 may serve as a potential biomarker for the prognosis of this malignancy.

MicroRNA dysregulation in gastric cancer: a new player enters the game

Gastric carcinogenesis is a multistep process involving genetic and epigenetic alteration of protein-coding proto-oncogenes and tumor-suppressor genes. Recent discoveries have shed new light on the involvement of a class of noncoding RNA known as microRNA (miRNA) in gastric cancer. A substantial number of miRNAs show differential expression in gastric cancer tissues. Genes coding for these miRNAs have been characterized as novel proto-oncogenes and tumor-suppressor genes based on findings that these miRNAs control malignant phenotypes of gastric cancer cells. In this connection, miRNA dysregulation promotes cell-cycle progression, confers resistance to apoptosis, and enhances invasiveness and metastasis. Moreover, certain polymorphisms in miRNA genes are associated with increased risks for atrophic gastritis and gastric cancer, whereas circulating levels of miRNAs may serve as biomarkers for early diagnosis. Several miRNAs have also been shown to correlate with gastric cancer progression, and thus may be used as prognostic markers. Elucidating the biological aspects of miRNA dysregulation may help us better understand the pathogenesis of gastric cancer and promote the development of miRNA-directed therapeutics against this deadly disease.

Evidence for an anomalous like-sign dimuon charge asymmetry

We measure the charge asymmetry A ≡ (N++ - N--)/(N++ + N--) of like-sign dimuon events in 6.1 fb-1 of pp collisions recorded with the D0 detector at a center-of-mass energy square root(s) = 1.96   TeV at the Fermilab Tevatron collider. From A we extract the like-sign dimuon charge asymmetry in semileptonic b-hadron decays: A(sl)(b) = -0.009 57 ± 0.002 51(stat) ± 0.001 46(sys). It differs by 3.2 standard deviations from the standard model prediction A(sl)(b)(SM) = (-2.3(-0.6)(+0.5)) × 10(-4), and provides first evidence of anomalous CP violation in the mixing of neutral B mesons.

Molecular characterisations of Pseudomonas syringae pv actinidiae strains isolated from the recent outbreak of bacterial canker on kiwifruit in Italy

Pseudomonas syringae pv actinidiae (Psa) is the causal agent of bacterial canker on kiwifruit a disease that affects both Actinidia deliciosa and A chinensis This disease has been reported in Japan Korea and Italy It has never been found in New Zealand An outbreak of bacterial canker on kiwifruit has been recently reported in Latina Italy Strains isolated from this outbreak were compared with strains isolated from Japan Korea and strains isolated from Italy in 1992 The specificity of the primers PsaF1/R2 and their usefulness in identifying strains of Psa were confirmed in this study Fingerprinting by BOXPCR allowed the distinction of strains of Psa tested from strains of the closely related pathovar theae However two different profiles were obtained for strains of Psa Two haplotypes for the housekeeping gene cts (gltA) were also found among strains of Psa Such variability might be used for further epidemiological studies