Surface and Pores of Silica Gels as a State of Colloidal Aggregation

The state of aggregation and ageing of colloidal silicas was studied in view of the behaviour of silanol groups, by means of thermodynamic, mechanical, ir spectroscopic and chemical methods. A close relationship was found between surface areas, porosities, and other properties of hydrothermally, thermally and chemically treated silicas, and the species and their populations of silanol groups.

Identification of a naturally processed HLA-Cw7-binding peptide that cross-reacts with HLA-A24-restricted ovarian cancer-specific CTLs

Here, we describe an human leukocyte antigen (HLA)-A*24:02-restricted cytotoxic T-lymphocyte (CTL) clone, 1G3, established from naïve CD8(+) T-lymphocytes obtained from a healthy donor stimulated with HLA-modified TOV21G, an ovarian cancer cell line. The 1G3 clone responds not only to ovarian cancer cells in the context of HLA-A*24:02 but also to allogeneic HLA-Cw*07:02 molecules through cross-reactive T-cell receptor recognition. Expression screening using a complementary DNA library constructed from TOV21G messenger RNA revealed that this alloreactivity was mediated through the nine-mer peptide VRTPYTMSY, derived from RNA-binding motif protein 4. To our knowledge, this study presents the first example of the allorecognition of an HLA-Cw molecule by HLA-A-restricted T-cells, thereby revealing a naturally processed epitope peptide. These findings provide the structural bases for the allorecognition of human T-cells. In addition, this study suggests that unexpected alloresponses occur in certain HLA combinations, and further study is needed to understand the mechanisms of alloreactivity for better prediction of alloresponses in clinical settings.

The 2014 liver ultrasound tracking benchmark

The Challenge on Liver Ultrasound Tracking (CLUST) was held in conjunction with the MICCAI 2014 conference to enable direct comparison of tracking methods for this application. This paper reports the outcome of this challenge, including setup, methods, results and experiences. The database included 54 2D and 3D sequences of the liver of healthy volunteers and tumor patients under free breathing. Participants had to provide the tracking results of 90% of the data (test set) for pre-defined point-landmarks (healthy volunteers) or for tumor segmentations (patient data). In this paper we compare the best six methods which participated in the challenge. Quantitative evaluation was performed by the organizers with respect to manual annotations. Results of all methods showed a mean tracking error ranging between 1.4 mm and 2.1 mm for 2D points, and between 2.6 mm and 4.6 mm for 3D points. Fusing all automatic results by considering the median tracking results, improved the mean error to 1.2 mm (2D) and 2.5 mm (3D). For all methods, the performance is still not comparable to human inter-rater variability, with a mean tracking error of 0.5–0.6 mm (2D) and 1.2–1.8 mm (3D). The segmentation task was fulfilled only by one participant, resulting in a Dice coefficient ranging from 76.7% to 92.3%. The CLUST database continues to be available and the online leader-board will be updated as an ongoing challenge.

TYK2 Promoter Variant and Diabetes Mellitus in the Japanese

BACKGROUND

Recently, natural mutation of Tyrosine kinase 2 (Tyk2) gene has been shown to determine susceptibility to murine virus-induced diabetes. In addition, a previous human genome-wide study suggested the type 1 diabetes (T1D) susceptibility region to be 19p13, where the human TYK2 gene is located (19p13.2).

METHODS

Polymorphisms of TYK2 gene at the promoter region and exons were studied among 331 healthy controls, and 302 patients with T1D and 314 with type 2 diabetes (T2D) in the Japanese.

FINDINGS

A TYK2 promoter haplotype with multiple genetic polymorphisms, which are in complete linkage disequilibrium, named TYK2 promoter variant, presenting decreased promoter activity, is associated with an increased risk of not only T1D (odds ratio (OR), 2.4; 95% confidence interval (CI), 1.2 to 4.6; P = 0.01), but also T2D (OR, 2.1; 95% CI, 1.1 to 4.1; P = 0.03). The risk is high in patients with T1D associated with flu-like syndrome at diabetes onset and also those without anti-glutamic acid decarboxylase autoantibody.

INTERPRETATION

The TYK2 promoter variant is associated with an overall risk for diabetes, serving a good candidate as a virus-induced diabetes susceptibility gene in humans.

FUNDING

Ministry of Education, Culture, Sports, Science and Technology and of Health, Labor and Welfare of Japan.

Synovial mesenchymal stem cells promote healing after meniscal repair in microminipigs

OBJECTIVE

The induction of synovial tissue to the meniscal lesion is crucial for meniscal healing. Synovial Mesenchymal stem cells (MSCs) are an attractive cell source because of their high proliferative and chondrogenic potentials. We examined whether transplantation of synovial MSCs promoted healing after meniscal repair of extended longitudinal tear of avascular area in a microminipig model.

DESIGN

Longitudinal tear lesion was made in medial menisci and sutured in both knees, and then a synovial MSC suspension was administered for 10 min only in unilateral knee. The sutured meniscus was evaluated morphologically and biomechanically at 2, 4, and 12 weeks. The behavior of transplanted MSCs was also examined.

RESULTS

The meniscal healing at 12 weeks was significantly better in the MSC group than in the control group; macroscopically, histologically and by T1rho mapping analysis. Transmission electron microscopic analysis demonstrated that the meniscus lesion was occupied by dense collagen fibrils only in the MSC group. Biomechanical analysis revealed that the tensile strength to failure of the meniscus higher in the MSC group than in the control group in each microminipig. Synovial tissue covered better along the superficial layer from the outer zone into the lesion of the meniscus in the MSC group at 2 and 4 weeks in each microminipig. Synovial MSCs labeled with ferucarbotran were detected in the meniscus lesion and adjacent synovium by MRI at 2 weeks.

CONCLUSION

Transplantation of synovial MSCs promoted healing after meniscal repair with induction of synovium into the longitudinal tear in the avascular zone of meniscus in pigs.

Platelet-dependent serum factor that stimulates the proliferation of epidermal cells in vitro

Agglutinated platelets are known to release a factor that stimulates the growth of arterial smooth muscle cells or dermal fibroblasts. The present study was designed to see the effect of this platelet factor on epidermal cells. The growth of cultured epidermal cells and dermal fibroblasts obtained from guinea pig ear skin was observed using 10% platelet-rich serum or platelet-poor serum in the culture medium. These sera were prepared from fresh human blood according to the method described by Ross. The cell growth was checked by counting the number of cells in culture or by the uptake of labeled thymidine by the cells. The platelet-rich serum significantly stimulated the growth of epidermal cells as well as fibroblasts as compared with the platelet-poor serum. This implies that platelet factor released after injury to cutaneous vessels in trauma or inflammation plays an important role in initiating proliferation of epidermal cells and dermal fibroblasts.

Preferable sites and orientations of transgene inserted in the adenovirus vector genome: The E3 site may be unfavorable for transgene position

The adenovirus vector (AdV) can carry two transgenes in its genome, the therapeutic gene and a reporter gene, for example. The E3 insertion site has often been used for the expression of the second transgene. A transgene can be inserted at six different sites/orientations: E1, E3 and E4 sites, and right and left orientations. However, the best combination of the insertion sites and orientations as for the titers and the expression levels has not sufficiently been studied. We attempted to construct 18 AdVs producing GFP or LacZ gene driven by the EF1α promoter and Cre gene driven by the α-fetoprotein promoter. The AdV containing GFP gene at E3 in the rightward orientation (GFP-E3R) was not available. The LacZ-E3R AdV showed 20-fold lower titer and 50-fold lower level of fiber mRNA than the control E1L AdV. Notably, we found four aberrantly spliced mRNAs in the LacZ-E3L/R AdVs, probably explaining their very low titers. Although the transgene expression levels in the E4R AdVs were about threefold lower than those in the E1L AdVs, their titers are comparable with that of E1L AdVs. We concluded that E1L and E4R sites/orientations are preferable for expressing the main target gene and a second gene, respectively.