Decreased ADAMTS13 Levels in Patients after Living Donor Liver Transplantation

Introduction

Thrombotic microangiopathy (TMA) is a complication occurring after liver transplantation (LT), and an unusually large multimer (ULM) of Von Willebrand factor (VWF) and ADAMTS13 may play an important role in the onset of TMA during LT.

Material and Methods

Eight-one patients underwent living donor LT (LDLT). Seventeen of those patients had both severe thrombocytopenia and hemolytic anemia with fragmented red cells and were diagnosed as TMA- like syndrome (TMALS).

Results and Conclusions

A significant reduction of ADAMTS13 and an increase of VWF were observed in the patients with TMALS. The ADAMTS13 activity in patients after LDLT was significantly reduced from day 1 to day 21, and it was significantly low in those with TMALS at day 14 and 28. The VWF levels in patients with LDLT were significantly high, and the VWF/ADAMTS13 ratio was significantly increased in patients at 7, 14 and 28 days after LDLT, especially in patients with TMALS at day 14 and 28 after LDLT. High molecular weight multimers of VWF were observed to have increased in patients with LDLT, and the high molecular weight multimers of VWF were further increased in those with mild TMALS but they decreased in those with severe TMA. These findings suggest that ULM- VWF and ADAMTS13 might be associated with the onset of TMA after LT.     

Association study of gender identity disorder and sex hormone-related genes

To investigate the biological mechanism of gender identity disorder (GID), five candidate sex hormone-related genes, encoding androgen receptor (AR), estrogen receptors α (ERα) and β (ERβ), aromatase (CYP19), and progesterone receptor (PGR) were analyzed by a case–control association study. Subjects were 242 transsexuals (74 male-to-female patients (MTF) and 168 female-to-male patients (FTM)), and 275 healthy age- and geographical origin-matched controls (106 males and 169 females). The distributions of CAG repeat numbers in exon 1 of AR, TA repeat numbers in the promoter region of ERα, CA repeat numbers in intron 5 of ERβ, TTTA repeat numbers in intron 4 of CYP19, and six polymorphisms (rs2008112, rs508653, V660L, H770H, rs572698 and PROGINS) of PGR were analyzed. No significant difference in allelic or genotypic distribution of any gene examined was found between MTFs and control males or between FTMs and control females. The present findings do not provide any evidence that genetic variants of sex hormone-related genes confer individual susceptibility to MTF or FTM transsexualism.     

Disruption of the midkine gene (Mdk) delays degeneration and regeneration in injured peripheral nerve

Midkine (MK) is a growth factor implicated in the development and repair of various tissues, especially neural tissues. MK acts as a reparative neurotrophic factor in damaged peripheral nerves. A postulated role of MK in the degeneration and regeneration of sciatic nerves was explored by comparing wild‐type (Mdk^+/+) mice with MK‐deficient (Mdk^?/?) mice after freezing injury. In the Mdk^?/? mice, a regenerative delay was observed, preceded by a decelerated Wallerian degeneration (WD). The relative wet weight of the soleus muscle slowly declined, and recovery was delayed compared with that in the Mdk^+/+ mice. In the regenerating nerve, unmyelinated axons were unevenly distributed, and some axons contained myelin‐like, concentrically lamellated bodies. In the endplates of soleus muscles, nerve terminals containing synaptic vesicles disappeared in both mice. In Mdk^?/? mice, the appearance of nerve terminals was delayed in synaptic vesicles of terminal buttons after injury. The recovery of evoked electromyogram was delayed in Mdk^?/? mice compared with Mdk^+/+ mice. Our results suggested a delay in axonal degeneration and regeneration in Mdk^?/? mice compared with Mdk^+/+ mice, and the delayed regeneration was associated with a delayed recovery of motor function. These findings show that a lack of MK following peripheral nerve injury is a critical factor in degeneration and regeneration, and manipulation of the supply of MK may offer interesting therapeutic options for the treatment of peripheral nerve damage. © 2009 Wiley‐Liss, Inc.     

Mechanisms for split localization of Fgf10 expression in early lung development

In early lung development, epithelial tubes (lung buds) intrude into mesenchyme covered with pleural cells (lung border), and form tree‐like networks, by means of repeated use of morphogenetic processes: “elongation,” “terminal bifurcation,” and “lateral budding.” When a bud is elongating, a peak of Fgf10 expression is formed in the mesenchyme near the tip; whereas when terminal bifurcation and lateral budding occur, two separate peaks are formed instead. To explain the spatial pattern of Fgf10 expression, we developed a mathematical model for the regulation of Fgf10 expression with geometrical conditions including shapes of the lung buds and the lung border. Different localization patterns of Fgf10 expression can be explained by the geometrical conditions. Fgf10 expression has a single peak when a length between the tip of lung bud and the lung border is large. When the length is small, Fgf10 expression has two peaks, whose location depends on the curvature of lung border. Developmental Dynamics 238:2813–2822, 2009. © 2009 Wiley‐Liss, Inc.     

Roundabout 4 is expressed on hematopoietic stem cells and potentially involved in the niche-mediated regulation of the side population phenotype

Roundabout (Robo) family proteins are immunoglobulin-type cell surface receptors that are expressed predominantly in the nervous system. The fourth member of this family, Robo4, is distinct from the other family members in that it is expressed specifically in endothelial cells. In this study, we examined the expression of Robo4 in hematopoietic stem cells (HSCs) and its possible role in HSC regulation. Robo4 mRNA was specifically expressed in murine HSCs and the immature progenitor cell fraction but not in lineage-positive cells or differentiated progenitors. Moreover, flow cytometry showed a correlation between higher expression of Robo4 and immature phenotypes of hematopoietic cells. Robo4(high) hematopoietic stem/progenitor cells presented higher clonogenic activity or long-term repopulating activity by colony assays or transplantation assays, respectively. A ligand for Robo4, Slit2, is specifically expressed in bone marrow stromal cells, and its expression was induced in osteoblasts in response to myelosuppressive stress. Interestingly, overexpression of Robo4 or Slit2 in HSCs resulted in their decreased residence in the c-Kit(+)Sca-1(+)Lineage(-)-side population fraction. These results indicate that Robo4 is expressed in HSCs, and Robo4/Slit2 signaling may play a role in HSC homeostasis in the bone marrow niche.     

Detection of M2 macrophages and colony-stimulating factor 1 expression in serous and mucinous ovarian epithelial tumors

Tumor-associated macrophages (TAM) are known to possess the immunosuppressive M2 macrophage phenotype. They contribute to tumor growth, invasion, and metastasis by producing various mediators. Macrophages, especially M2 polarized macrophages, preferentially express CD163 and CD204, but few studies have investigated macrophage phenotypes in human ovarian tumors. The purpose of the present study was therefore to present results on macrophage differentiation in human ovarian serous and mucinous epithelial tumors. The method focused on immunostaining of paraffin-embedded tumor samples. Almost all macrophages infiltrating tumor tissues expressed CD163 and CD204, indicating the phenotypic shift toward M2 macrophage. The numbers of CD68-positive macrophages as well as of CD163- and CD204-positive macrophages in borderline and malignant tumors were significantly higher than in benign tumors. They correlated well with histological gradient of malignancy. Macrophage colony-stimulating factor (also known as colony-stimulating factor; CSF-1), which is one of the cytokines considered to induce TAM to polarize toward an M2 phenotype, was then evaluated. CSF-1 expression in malignant tumor cells was significantly higher than that in benign tumor cells and correlated with histological malignancy. These results suggest that CSF-1 derived from tumor tissues induces macrophages to shift toward the M2 phenotype, which is considered to promote tumor growth.     

Genome-wide histone methylation profile for heart failure

Epigenetic alterations are implicated in the development of cardiac hypertrophy and heart failure, but little is known of which epigenetic changes in which regions of the genome play such a role. We now show that trimethylation of histone H3 on lysine-4 (K4TM) or lysine-9 (K9TM) is markedly affected in cardiomyocytes in association with the development of heart failure in a rat disease model. High-throughput pyrosequencing performed with ChIP products for K4TM or K9TM prepared from human left ventricular tissue with retained or damaged function also revealed that protein-coding genes located in the vicinity of K4TM marks differ between functional and disabled myocytes, yet both sets of genes encode proteins that function in the same signal transduction pathways for cardiac function, indicative of differential K4TM marking during the development of heart failure. However, K9TM mark-profile was less dependent on the disease status compared to that of K4TM. Our data collectively reveal global epigenetic changes in cardiac myocytes associated with heart failure.     

Chemosensitivity and Survival in Gastric Cancer Patients with Microsatellite Instability

Introduction  Conflicting data exist regarding the relevance of high-frequency microsatellite instability (MSI-H) for predicting the prognosis and benefits of 5-fluorouracil (5-FU)-based chemotherapy. This study investigated the usefulness of MSI as either a prognostic indicator or predictor of distinct clinical attributes regarding the use of adjuvant chemotherapy with 5-FU and its analogues in gastric cancer. Materials and methods  Data and tumor specimens were collected from 240 gastric cancer patients from 1993 to 2002. Five microsatellite loci were analyzed using a high-intensity microsatellite analysis reported previously. A Cox proportional hazard model was used to compare the clinical data and survival as well as any associations between MSI and 5-FU treatment status of patients with MSI or microsatellite stability (MSS) gastric cancers. A 3-(4,5-dimethyl-2-thiazolyl) -2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was conducted in 168 cases to investigate chemosensitivity to 5-FU. Results  This analysis identified 22 MSI-H (9.4%), 25 MSI-L (10.7%), and 193 MSS (79.9%) tumors. Gastric cancer with MSI-H tended to have increased likelihood to show higher age, antral location of the tumor, and lymph vessel involvement (P < 0.05). Univariate analyses failed to show any difference between the MSI-H and MSS/MSI-L groups with respect to overall survival. Furthermore, survival after the administration of 5-FU did not correlate with MSI status, and MSI was not associated with 5-FU sensitivity by MTT assay. Conclusion  The results of this study indicate that MSI status has no clear influence on overall survival or response to 5-FU in gastric cancer.