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Abstract: The rostro-caudal patterning within a somite is periodically established in the presomitic mesoderm (PSM). In the mouse, Mesp2 is required for the rostral property whereas Notch signaling and Ripply2, a Mesp2-induced protein that suppresses Mesp2 transcription, are required for the caudal property. Here, we examined the mechanism behind rostro-caudal patterning by comparing the spatial movement of Notch activity with Mesp2 protein localization in wild-type embryos and those defective in Ripply1 and 2, both of which are expressed in the PSM. Mesp2 protein appears first as a thin band in the middle of the traveling Notch active domain in both wild-type and Ripply1/2-deficient embryos. In wild-type embryos, the Mesp2 band expands anteriorly to the expression front of Tbx6, an activator of Mesp2 transcription. Notch activity becomes localized further anteriorly to this Mesp2 domain, but does not pass over the anterior Mesp2 domain generated in the previous segmentation cycle. As a result, the Notch active domain appears to be restricted between these two Mesp2 domains. In Ripply1/2-deficient embryos, the Mesp2 band becomes more expanded and the Notch domain is finally diminished. Interestingly, Ripply1/2-deficient embryos exhibit anterior expansion of the Tbx6 protein domain, suggesting that Ripply1/2 regulates Mesp2 expression by modulating elimination of Tbx6 proteins. We propose that the rostro-caudal pattern is established by dynamic interaction of Notch activity with two Mesp2 domains, which are defined in successive segmentation cycles by Notch, Tbx6 and Ripply1/2. [Copyright &y& Elsevier]

To elucidate whether myocardial CD38/cyclic ADP-ribose (cADPR) signaling plays a physiological role, we investigated the heart of CD38 knockout mice (CD38KO). In CD38KO, the myocardial cADPR content was reduced by 85% compared with wild-type mice (WT). Cardiac hypertrophy developed only in males. At 36 °C, none of the parameters for Ca2+ transients and forces of the papillary muscles differed between WT and CD38KO. In contrast, at 27 °C, at which cADPR does not work, the peak [Ca2+]i was increased and the decline in [Ca2+]i was accelerated in CD38KO compared with WT. In CD38KO, the protein expression of SR Ca2+ ATPase type2 (SERCA2) and the SERCA2-to-phospholamban ratio were increased compared with WT. The ryanodine receptor protein was increased only in female CD38KO compared with WT. These data suggest that the CD38/cADPR signaling plays an important role in intracellular Ca2+ homeostasis in cardiac myocytes in vivo. Its deficiency was compensated differentially according to gender. [Copyright &y& Elsevier]

To obtain a detailed distribution of modulus for fine finite element (FE) simulation of carbon fiber-reinforced thermoplastic, a non-destructive vibrational method is proposed by considering the tested natural frequencies as iteration targets and using genetic algorithm to update the modulus in the FE model. Mass blocks are attached using various distributions to create supplemental constraints. Two strategies of integrating multiple models to increase the constraints and narrowing down the search range and reset the initial values to avoid local optimum are applied to increase the inverse accuracy. The average absolute error (AAE) reached 8.5 % by integrating plates with various block-adding methods and was reduced to 5.2 % by Re-Search strategy. The real plate made of sheet molding compounds demonstrated the validity of the proposed method, and the final AAE was 8.8 % owing to the impact of the interface and imperfect geometry information. A hat-shaped structure with inversed AAE of 9.3% proved the feasibility for complex structures, which provides a promising application of complex components in the automobile industry. [ABSTRACT FROM AUTHOR]

Abstract: The vertebrae are derived from the sclerotome of somites. Formation of the vertebral body involves a process called resegmentation, by which the caudal half of a sclerotome is combined with the rostral half of the next sclerotome. To elucidate the relationship between resegmentation and rostro-caudal patterning of somite, we used the Uncx4.1-LacZ transgene to characterize the resegmentation process. Our observations suggested that in the thoracic and lumbar vertebrae, the Uncx4.1-expressing caudal sclerotome gave rise to the intervertebral disc (IVD) and rostral portion of the vertebral body (VB). In the cervical vertebrae, the Uncx4.1-expressing caudal sclerotome appeared to contribute to the IVD and both caudal and rostral ends of the VB. This finding suggests that the rostro-caudal gene expression boundary does not necessarily coincide with the resegmentation boundary. This conclusion was supported by analyses of Mesp2 KO and Ripply1/2 double KO embryos lacking rostral and caudal properties, respectively. Resegmentation was not observed in Mesp2 KO embryos, but both the IVD and whole VB were formed from the caudalized sclerotome. Expression analysis of IVD marker genes including Pax1 in the wild-type, Mesp2 KO, and Ripply1/2 DKO embryos also supported the idea that a metameric pattern of IVD/VB is generated independently of Mesp2/Ripply-mediated rostro-caudal patterning of somite. However, in the lumbar region, IVD differentiation appeared to be stimulated by the caudal property and suppressed by the rostral property. Therefore, we propose that rostro-caudal patterning of somites is not a prerequisite for metameric patterning of the IVD and VB, but instead required to stimulate IVD differentiation in the caudal half of the sclerotome. [Copyright &y& Elsevier]

Abstract: To delineate a surgical strategy for long-term intractable epilepsy associated with nonmalignant brain tumor, we developed a protocol for 25 patients whereby removal of tumor alone and additional irritative peritumoral tissue between sulci (gyrectomy), as well as further resectioning, was performed based on intraoperative electrocorticogram results. In five patients, no irritative zones were observed that required resectioning following complete removal of tumors. Additional gyrectomy was indicated in 18 patients who demonstrated gliosis or cortical dysplasia in the peritumoral residual irritative zone. Remote irritative zone observed in two patients was correlated with long-term and frequent seizures. During a follow-up period of at least 5 years, seizure outcome was Engel category I in 92%, and all patients have remained tumor-free. Peritumoral gyrectomy as a means of removing likely epileptic tissue following tumor resection appears to be a useful method for treating long-term intractable tumoral epilepsy. Further resectioning of remote tissue should be considered in patients with severely intractable seizures. [Copyright &y& Elsevier]

The regulator of fibroblast growth factor 2 (FGF-2) transcription (RFT) has been reported to be a transcriptional repressor of FGF-2 and induce glioma cell death by its overexpression. Here we report that RFT regulates cell cycle as well as apoptosis by a novel mechanism. RFT expressed in some glioma cell lines, U138MG and T98G, but neither in U87MG nor U251MG. Overexpressed RFT-induced apoptosis in U87MG and U138MG with functioning-type p53 but neither in U251MG nor T98G with non-functioning-type p53. Administration of FGF-2 failed to prevent RFT-induced apoptosis. Overexpression of RFT caused G1–S arrest and upregulated both the phosphorylation of p53 at Ser-15 and the expression level of p21Waf1. Furthermore, RNAi knockdown of p53 abolished RFT-induced apoptosis in U87MG. Taken together, our results support that RFT regulates G1–S transition and apoptosis via p53/p21Waf1 pathway. [Copyright &y& Elsevier]

Abstract: Neuropoietin (NP) is a recently identified member of the interleukin (IL)-6 family of cytokines, which share glycoprotein 130 (gp130) as a signal-transducing receptor component, and is highly expressed in embryonic brain. In this study, we show that NP has the potential to induce neuroepithelial cells to differentiate into astrocytes. NP stimulation leads to promoter activation of the gene for an astrocyte marker, glial fibrillary acidic protein (GFAP), which is clearly inhibited by either expression of a dominant-negative form of a transcription factor, signal transducer and activator of transcription 3 (STAT3) or by a nucleotide-substitution in the STAT3-binding element within the gene promoter. We further show that NP induces binding of endogenous STAT3 to its cognate sequence within the gfap gene promoter in neuroepithelial cells. Moreover, like the other IL-6 cytokine family members, NP promotes astrocyte differentiation in a synergistic manner with bone-morphogenetic protein (BMP)-2. Taken together, our data indicate that NP can be considered as a new astrocyte-inducing cytokine in the developing brain. [Copyright &y& Elsevier]

Abstract: To examine the involvement of diacylglycerol kinase (DGK) and phosphatidic acid phosphatase (PAP) in pressure overloaded cardiac hypertrophy, rats were subjected to either ascending aortic banding for 3, 7, and 28 days or sham operation. In comparison with sham-operated rats, the left ventricular (LV) weight of the aortic-banded rats increased progressively. At 28 days after surgery, the expression of DGKε mRNA but not DGKζ or PAP2b mRNA in the LV myocardium significantly decreased in the aortic-banded rats compared with the sham-operated rats. DGKζ protein in the LV myocardium translocated from the particulate to the cytosolic compartment in the aortic-banded rats. Furthermore, the myocardial content of 1,2-diacylglycerol and PKCδ protein expression in the particulate fraction of the LV myocardium significantly increased in aortic-banded rats compared with sham-operated rats. These results suggest that DGKε and DGKζ play distinct roles in the development of pressure overloaded cardiac hypertrophy and that the two isozymes are differentially regulated. [Copyright &y& Elsevier]

Abstract: Immunohistochemical cell proliferation analyses have come into wide use for evaluation of tumor malignancy. Topoisomerase IIα (topo IIα), an essential nuclear enzyme, has been known to have cell cycle coupled expression. We here show the usefulness of quantitative analysis of topo IIα mRNA to rapidly evaluate cell proliferation in brain tumors. A protocol to quantify topo IIα mRNA was developed with a real-time RT-PCR. It took only 3h to quantify from a specimen. A total of 28 brain tumors were analyzed, and the level of topo IIα mRNA was significantly correlated with its immuno-staining index (p<0.0001, r=0.9077). Furthermore, it sharply detected that topo IIα mRNA decreased in growth-inhibited glioma cell. These results support that topo IIα mRNA may be a good and rapid indicator to evaluate cell proliferate potential in brain tumors. [Copyright &y& Elsevier]